Wednesday, 30 October 2024

TEST PAPER - (W.B) SCIENCE+ MATHS

TEST PAPER 1 

Time: 3 hours 15 minutes.       Full Marks: 90

Group - A
(Answer to all questions is compulsory)

1. Write the answer in complete sentence by choosing the correct answer for each question with respective serial number.      1x 15=15
a) Select from the following the term that describes the movement in the leaves of Sundew
i) photonastic ii)  thermnostic iii) Chemonastic iv) seismonastic

b) Find the hormone that is found in juice of tomato
i) Auxin ii) Gibberellin iii) cytokinin  iv) Florigen

c) Identify the hormone popularity called the maternity hormone
i) Oestrogen ii) progesterone iii) prolactin iv) testosterone 

d) Choose the phase of mitosis during which the chromosomes are arranged on the equator of the cell 
i) prophase ii) metaphase iii) anaphase iv) telophase 

e) Identify the part from which fruit is formed after fertilization
i) stigma ii) ovary iii) ovule iv) ovum

f) The age from 11 to 19 years in humans is called 
i) teenage ii) adulthood iii) adolescence iv) senescence 

g) Laws of heredity has been proposed by 
i) Lamarck ii) Darwin iii) Mendel iv) Miller 

h) Calculate how many types of gametes are formed from guinea-pig having genotype Bbrr 
i) 1 ii) 2 iii) 4 iv) 3

i) Identify the nature of hydrophilia 
i) sex linked dominant 
ii) autosomal dominant 
iii) sex linked recessive 
iv) autosomal recessive 

j) Select the propounded on the theory of "inheritance of acquired characters " from the following 
i) Lamarck ii) Darwin iii) Mendel iv) Weisman 

k) Recollect from your memory the oldest fossil of horse 
i) pliohippus ii) Merychippus iii) Mesohippus iv) Eohippus

l) Determine the following the one which according to you is not a vestigial organ is
i) Finger of hand ii) Veriform Appendix iii) Wings of ostrich iv) Coccyx 

m) Identify the bacteria which you think converts the nitrogenous waste or dead bodies into ammonia 
i) Nitrosomonas ii) Bacillus mycoides iii) Nitrobacter iv) Thioabecillus

n) Select out of the following the one which is not chronic disease of lung
i) bronchitis ii) asthma iii) fever iv) lung cancer 

o) Select from the following the one that is not in-situ conversation 
i) National park ii) sanctuary iii) zoo iv) biosphere reserve 

Group B 
2. Answer 21 questions out of 26 questions given as below instructed.    (1x 21=21)
 Fill in the blanks with proper words in the following sentences from (any five) (1x5= 5)
 
a) ____ is secreted from islets of Langehans of pancreas.
b) According to you ____synthesis protein of the cell during cell division.
c) Hemophilia father's daughter is always____ of hemophilia.
d) Crocodile is considered to be advanced in evolution over other reptiles as it has a ___ chamberd heart.
e) if you visit a place with maximum biodiversity, you will be able to consider it to be a ___
f) Due to requirement of reserpine for treatment of high blood pressure, the plant is becoming extinct due to overuse.

Decide whether the following statements are true or false (any five)   1x5= 5
g) if a person cannot see nearby objects p, he needs to use concave lens.
h) In a base pairing Adenine binds to Thymine.
i) Austosmo are responsible for sex stimulation in human beings.
j) Darwin wrote the book 'Origin of Species By means of Natural Selection'
k) Azotobacter is a denitrifying bacteria.
l) Auxin helps in tropic movement in plants.

Match the words in column A with those which are most appropriate in column B & rewrite the correct pair mentioning the serial number of both (any five)   1x5= 5
Column A 
A) Ciliary locomotion 
B) Fragmentation 
C) Tt
D) Wings of birds and butterflies 
E) Singalila National Park 
F) Pollinating agent

Column B 
i) honey bee 
ii) hybrid tall plants
iii) analogous organ 
iv) Paramecium
v) Red panda 
vi) spirogyra 
vii) homologous organ 

Answer in a single word or in a single sentences (any six).    1x6=6
m) Choose the odd one and write it:
STH, ACTH, ADH, GTH
n) Write one function of a Ganglion 
o) A pair of related terms is given below on the basis of the relationship in the first pair write the suitable word in the gap of 2nd pair 
DNA: Thymine: : RNA: ____
p) What is the ratio of plants in F₁ generation when a hybrid tall plant is crossed with pure dwarf one?
q) Determine the type of gametes that can be obtained from a female human being.
r) How many airsac are present in pigeon ?
s) Amongs the following four terms one includes the other three . Find out them term and write it--
Nitrogen cycle, Nitrification, Denitrification, Ammonification


Group - C
3. Answer any 12 questions in 2-3 sentences out of 17 questions given below : 2x12= 24
a) How does cytokinin affect plant growth ?
b) On the basis of the following points distinguish between Axon and dendron:
         i) Structure  ii) function 
c) State two purposes of locomotion 
d) Explain how flexion and extension are opposite in action.
e) Name an animal and plant where reproduction occurs by budding.
f) What do you mean by fertilization in plants ?
g) Explain how cross pollination is different from self pollination regarding use of pollinating agents and characters of offspring produced.
h) "Male is considered as heterogametic sex"-  justify the statement.
i) if husband is normal and wife is carrier of Thalassemia , what may happen to their four children?
j) Write down the law that Mendel inferred by performing the experiment on pure tall and pure dwarf pea plant.
k) Mention two significances of fossils in evolution.
l) State the importance of airsacs of birds.
m) Why do you consider the following structure are important
    i) swim bladder in rohu fish  ii) salt glad in Sundari plant 
n) Assess why SPM is so harmful to human health.
o) name the biodiversity hotspots which lie in India.
p) Explain why Cryopreservation is to important for conserving endangered species.
q) JFM is helpful to protect, conserve and flourish our forest reserve- Explain how.

Group D
(Long Answer Type Question)

4) write the 6 question or their alternatives given below. The make allotted for each questions is 5
( the division of make is either 3 + 2, 2 + 2 or 5)         5x6= 30

a) Draw a neat diagram of a neurone and label the following parts:  (2+3=5)
  i) Dendrite ii) Axon iii) Schwann cell iv) Node of Ranvier 
OR
Draw a neat diagram of anaphase stage of animal cell division and label the following parts.
    i) Chromatid  ii) Centrosome iii) Continuous fibre iv) Chromosomal fibre 

b) Write chemical composition of chromosome. "Amitosis is known as direct cell division". Explain with the help of an example.         (2+3=5)
OR
 What do you understand by alteration of generation?  Explain the phase of growth in living things.

c) Why Mendel selected pea plant for his experiment ? Explain incomplete dominance with checker board.       2+3=5
OR
A patient has come with certain symptoms. How will you identify that he is suffering from Hemophilia ? Write the name of organs affected in a Thalassemia patient.

d) Illustrate with diagram how the hearts of vertebrates explain the evolution theory.  5
OR
 What are the advantages of oval RBC in camel to live in dry desert condition ? How are analogous organs and homologous organs different from each other ?

e) What is biomagnification ? Explain with suitable example how does it happen, in and aquatic food chain.       (3+2=5)
OR
Analyse three major environment to problems of the Sundarbans with their impacts on biodiversity. Compare between Wildlife sanctuary and Biosphere Reserve.

f) Through Sundarban has been recognised as a biosphere reserved it is gradually decreasing in size and facing some severe environmental problems.  Elaborate upon this topic with suitable examples.          5
OR
Explain the following terms:
i)  acid rain 
ii) global warming
iii) Deafness 
iv) Endemic Species 
v) Poaching 

Sunday, 27 October 2024

TEST PAPER - SCIENCE+ MATHS- X


1- Mark Questions 

A)
1) How is the vapour density of a gas related to the relative molecular mass of the gas ?

2) What is the molar volume of hydrogen ?

3) What is the empirical formula of fructose (C₆H₁₂O₆)?

4) What is the mass of 1 mole of carbon ?

5) What is the value of molar volume of a gas at STP 22.4 ?

6) Differentiate between 2H and H₂.

7) When gases react together , their reaction volumes bear a simple ratio to each other under the same conditions of temperature and pressure. Who proposed this gas law?

8) The gases hydrogen, oxygen, carbon dioxide, sulphur dioxide and chlorine are arranged in order of their increasing relative molecular masses.
Given 8g of each at STP, which gas will contain the least number of molecules and which will the most ?

9) Define atomic weight.


B) Numericals based on percentage composition, Empirical Formula and Molecular Formula 

1) Calculate the percentage of Nitrogen in Ammonium Nitrate(NH₄NO₃). 

2) The molecular formula of an organic acid is H₂C₂O₂. What is its empirical formula ?

3) Calculate the percentage of Nitrogen in almunium nitride.(Al=27, N=14). 

4) Calculate the percentage of sodium in sodium aluminium fluoride(Na₃AlF₆) correct to the nearest whole number (F=19; Na=23; Al= 27). 


C) Choose the correct answer 

1) Molecular mass of benzene (C₆H₆) is 
a) 58 amu b) 68 amu c) 78 amu d) 468 amu

2) The number of atoms in 12g of ¹²₆C is 
a) 12 b) 6.023 x 10²³ c) 6 d) 6.023 x 10⁻²³ 

3) One mole of CO₂ contains 
a) 6.023 x 10²³ atoms of O
b) 3g of atom of CO₂
c) 6.023 x 10²³ atoms of C
d) 8g atoms of CO₂ 

4) The percentage of oxygen in H₂O is 
a) 8.88% b) 20.0% c) 80.0% d) 88.88%

5) The percentage of hydrogen in H₂O is 
a) 8.88% b) 11.11% c) 20.60% d) 80.0%

6) A compound was found in the contains 5.37% nitrogen. What is the minimum molecular weight of the compound ?
a) 260.7g b) 26.07 g c) 2.607 g d) None 

7) The formula which represents the simple ratio of atoms in a compound is called :
a) emperical formula 
b) molecular formula
c) structural formula
d) rational formula 

8) The empirical formula of a compound is CH. The molecular weight of the compound is 78. Its molecular formula will be:
a) C₂H₂ b) C₃H₃ c) C₄H₄ d) C₆H₆

9) Two elements A (at.wt. 75) and B(at.wt. 16) combine to yield a compound. The percentage by weight of A in the compound was found to be 75.08. The formula of the compound is :
a) AB b) AB₃ c) A₂B d) A₂B₃

10) one mole of a compound contains one mole of C and two moles of O. The molecular weight of the compound is 
a) 3 b) 12 c) 32 d) 44

11) Mass of H₂O in 1000 kg is CuSO₄. 5H₂O is 
a) 3605g b) 360.5 g c) 36.05 d) 3.605g

12) 7 gram of carbon on Molecular oxidation produces :
a) 26g of CO₂
b) 14g of CO₂
c) 30g of CO₂
d) 42g of CO₂

13) The phosphate of a metal has the formula MPO₄. The formula of its chloride is:
a) MCl b) MCl₂ c) MCl₃ d) M₂Cl₂

14) A compound has the emperical formula C₂H₃O₂. Its vapour density is 59. its molecular formula will be :
a) C₂H₃O₂ b) C₄H₆O₄ c) C₆H₉O₆ d) C₈H₁₂O₈

15) The number of molecules present in 8 gram of O₂ gas is 
a) 6.023 x 10²³
b) 3.01 x 10²³
c) 12.044 x 10²³
d) 1.51 x 10²³

16) The number of atoms in 4.25 g of of NH₃is approximately 
a) 1.0 x 10²³
b) 1.5 x 10²³
c) 6.2 x 10²³
d) 6.02 x 10²³

17) 1 mole of CO₂ contains:
a) 6.02 x 10²³ atoms of C
b) 6.02 x 10²³ atoms of O
c) 6.2 x 10²³ molecules of CO₂ 
d) 3g atoms of CO₂ 

18) The number are moles in 0.224 litres of H₂ gas at STP (assuming ideal gas behaviour) is 
a) 1 b) 0.1 c) 0.01 d) 0.001

19) Mass of oxygen in 36g of pure water is 
a) 16g b) 64 g c) 70g d) 32g

20) 4.8 g of an element A (at..wt= 48) was combined with 3.2 g of an element B (at.wt= 16) to form an important industrial pigment. The formula of the pigment is
a) Ti₂O₃ b) Ti₂O c) TiO₂ d) TiO






2-Marks Questions 

1) Write the specific form of the mole definition for each of the following substance in the form one mole X= xxx g X.
a) iron.
b) chlorine.
c) sodium. 
d) chloride.

2) What do you understand by the following terms ?
a) mole
b) Avogadro's number 

3) Under the same conditions of temperature and pressure you collect 2 litres of carbon dioxide. 3 litres of chlorine, 5 litres of hydrogen. 4 litres of nitrogen and 1 litre of sulphur dioxide. In which gas sample will be there be:
a) the greatest number of molecules.
b) the least number of molecules ?

4) Carbon monoxide combines with oxygen to form carbon dioxide according to the following equation :
2CO + O₂ ---> 2CO₂
200 cm³ of carbon monoxide is mixed with 100 cm³ of oxygen at room temperature and ignited. Calculate the volume of carbon dioxide formed when the cooled to room temperature. What other gas. If any, may also be present ? 

5) The reaction between aluminium carbide and water takes place according to the following equation:
Al₄C₃ + 12H₂O----3CH₄ + 4Al(OH)₃
 Calculate the volume of Methane (CH₄) measured at STP. released from 14.4 g of aluminium carbide by excess of water. (C= 12, Al= 27). 

6) What volume of propane is burnt for every 100 cm³ of oxygen used in the reaction C₃H₈+ 5O₂ ---> 3CO₂ + 4H₂O ?
(gas volumes measured under the same conditions). 

7) What volume of oxygen would be required for the complete combustion of 100 litres of ethane according to the following equation ?
2C₂H₆ + 7O₂---> 4CO₂ + 6H₂O. 

8) The reaction 
4N₂O + CH₄ ---> CO₂ + 2H₂O + 4N₂
takes place in the gaseous state. If all volumes are measured at the same temperature and pressure, calculate the volume of dinitrogen oxide (N₂O) required to give 150 cm³ of steam. (N=14, O= 16, C=12, H=1). 

9) How many grams are there in :
a) 2 moles of molecular oxygen ? (O=16, N=14).
b) 0.01 mole of molecular Nitrogen ? 

10) How many mole atoms are there in:
a) 112g of iron ? (Fe= 56). 
b) 48 g of oxygen (O= 16). 

11) How many molecules are there in 1 litre of any gas at STP ? 

12) What volume is occupied by 10²⁴ molecules of Nitrogen, Oxygen and chlorine ? 

13) A 5 g sample of oxygen is in a container at STP . What is the volume of container ? 

14) 5000 molecules are present in 'V' volume of hydrogen at STP. Calculate the volume of Nitrogen gas which has 2.5x 10⁸ molecules at STP. 

15) 6 x 10²² molecules are present in 2.24 dm³ of chlorine at STP. Find the volume of SO₂ gas at STP . which has 3x 10¹⁹ molecules. 

16) Calculate the molecular weight of NH₄NO₃(O= 16, H=1, N= 14).

17) Calculate the weight of 10.0 gram atoms of sodium. 

18) Find the weight of 0.5 mole of O₂. 

19) Find the weight of 0.2 mole of H₂ gas. 

20) Find the number of particles in 0.1 mole of a substance. 

21) Which of the following would weight most ?
a) one mole of H₂O. 
b) one mole of CO₂. 
c) one mole of NH₃. 
d) one mole of CO. 

22) How many grams of Al are present in 0.2 mole of it ? 

23) What is the weight of 0.1 mole of HCL ? 

24) How many grams of H₂O are present in 0.2 mole of it ? 

25) What is the mass of 0.1 mole of CO₂ in grams ? 

26) From the equation N₂ + 3H₂O---> NH₃. Calculate the volume of ammonia gas formed when 6 litres of hydrogen react with excess nitrogen, all volumes measured at STP. 

27) Given that the relative molecular mass of copper oxide is 80. What volume of ammonia (measured at STP) is required to completely 120g of copper oxide?
The equation for the reaction is:
3CuO + 2NH₃ ---> Cu + 3H₂O + N₂ (Volume occupied by 1 mole of gas at STP is 22.4 litres). 

28) Find the total percentage of oxygen in magnesium nitrate crystals: Mg(NO₃)₂. 6H₂O.
(Mg=24, N=14, O=16, H=1).

29) Determine the empirical formula of the compound whose composition by mass is 42% nitrogen, 48% oxygen and 10% hydrogen. (H=1, N=14, O= 16).

30) Calculate the percentage of phosphorus in the fertilizer, superphosphate Ca(H₂PO₄)₂. 



3- Marks Questions 

1) Write the empirical formula of:
a) C₆H₆.
b) C₂H₂. 
c) CH₃COOH.

2) a) A vessel containing N molecules of oxygen at a certain temperature and pressure. How many molecules of Sulphur dioxide can the vessel accommodate at the same temperature and pressure? 
b) Each of two flasks contains 2.0g of gas at the same temperature and pressure. One flask contains oxygen and the other hydrogen.
i) which sample contains the greater number of molecules ? 
ii) If the hydrogen sample contains N molecules. How many molecules are present in oxygen sample ? 

3) Calculate the volume of HCl gases formed and chlorine gas required 40ml of methane react completely with chlorine as illustrated below. All measurements are made at the same temperature and pressure. CH₄+ 2Cl₂ ---> CH₂Cl₂(g)+ 2HCl(g). 

4) The gases --- chlorine, nitrogen Ammonia and Sulphur dioxide are collected under the same conditions of temperature and pressure. Copy the following table which gives the volumes of gases collected and the number of molecules in 20 litres of nitrogen. You have to complete the table giving the number of moleculars in the other gases in terms of X.
Gas Volume Number of molecules
chlorine 
nitrogen 
Ammonia 
Sulphur dioxide 


5) 560 ml of carbon monoxide is mixed with 500 ml of oxygen and ignited. The chemical equation for the reaction is as followed:
2CO + O₂ ---> 2CO₂
Calculate the volume of oxygen used and carbon dioxide formed in the above reaction. 

6) 16 g of Oxygen and 3g of hydrogen are mixed and kept in a vessel at 760 mm pressure at 0°C. What is the volume of the occupied by mixture ? 

7) Calculate the number of molecules in 0.71 g of chlorine gas. Take Avogadro's number as 6 x 10²³. (Cl= 35.5). 

8) Calculate the number of molecules in 3.65g of HCl. Take Avagadro's number as 6 x 10²³ (H=1, Cl=35.5). 

9) Calculate the weight of 10.0 atoms of sodium. (1 amu= 1.6603 x 10⁻²⁴ g). 

10) Calculate the weight in grams of 2 x 10²² molecules of copper sulphate. Take Avogadro's number as 6 x 10²³. (Cu=64, S= 32, O= 16). 

11) Calculate the weight in grams of 4 x 10²⁴ molecules of SO₃ gas. Take Avogadro's number as 6 x 10²³.

12) Find the number of molecules in 3.2g of SO₂.

13) Find the number of hydrogen atoms in 0.1 mole of H₂SO₄. 

14) Calculate the number of moles of CO₂ which contain 8g of O₂. 

15) Calculate the number of moles of Methane in 0.8 of it. 

16) Calculate the mass of one atom of the silver. 

17) Calculate the mass of 1 Molecule of Oxygen.

18) Calculate the number of oxygen atoms in 0.1 mole Na₂CO₃.

19) What amount of sulphuric acid will be required to dissolve 3g of magnesium carbonate?
MgCO₃ + H₂SO₄ ---> MgSO₄ + H₂O+ CO₂ (Mg=24, C=12, S=32, O= 16). 

20) How many litres of hydrogen will be liberated at STP when 2.8 g of iron react with sulphuric acid? (Fe=56, H=1). 1.12 litres

21) Ammonia may be oxidised to nitrogen monoxide in the presence of a catalyst according to the following equation:
4NH₃ + 5O₂ ---> 4NO + 6H₂O
If 27 litres of reacs are composr, what volume of nitrogen monoxide is produced at the same temperature and pressure? (H=1, N= 14, O= 16, P= 31).


21) Ammonia may be oxidised to nitrogen monoxide in the presence of a catalyst according to the following equation.
4NH₃ + 5O₂ ----> 4NO + 6H₂O
If 27 litres of reactants are consumed. What volume of nitrogen monoxide is produced at the same temperature and pressure 
(H= 1, N= 14, O= 16, P= 31).     

22) If 112 cm³ of hydrogen sulphide is mixed with 120 cm³  of chlorine at STP. What mass of Sulphur is formed ?
H₂S + Cl₂---> 2HCl + S.      

23) The reaction of potassium permanganet (VII) with acidified iron (II) sulphate is given below :
2KMnO₄ + 10 FeSO₄ + 8H₂SO₄ ---> K₂SO₄ + 2MnSO₄ + 5Fe₂(SO₄)₃+ 8H₂O
If 15.8 g of potassium permanganate (VII) was used in the reaction. calculate the mass of iron (II) sulphate used in above reaction.
(K= 39, Mn= 55, Fe= 56, S= 32, O=16).      

24) Determine the percentage composition of Al₂(SO₄)₃. (Al= 27, S= 32, O= 16).             

25) Determine the percentage composition of Ag₂CrO₄. (Ag= 107.9, Cr= 52, O= 16).       

26)  Determine the percentage composition of CuFeS₂. (Cu=63.5, Fe= 55.8, S= 32).   

27) Calculate the empirical formulas of a compound which has the following percentage composition: Na= 43.4%, C= 11.3% , O= 45.3% (Na= 23, C= 12, O= 16)..    

28) An organic salt gave the following percentage composition: Na= 29.11% , S= 40.51% and O= 30.38%
Calculate the empirical formula of the salt. (Na= 23, S= 32, O=16).   

29) The percentage composition of sodium phosphate as determined by analysis is 42.21% sodium, 18.9% phosphorus and 39% oxygen p. Find the empirical formula of the compound (work to two decimal places). (Na= 23, P= 31, O=16).  

30) Calculate the percentage of platinum in ammonium chloroplatinate . (NH₄)₂PtCl₆.
(give your answer correct to nearest whole number)
(N=14, H=1, Pt= 195, Cl= 35.5).   

31) An experiment showed that in a lead chloride solution, 6.21 g lead combined with 4.26g of chlorine. What is the empirical formula of this chloride ?
(PB = 207, Cl= 35.5).     

32) Determine the empirical formula of a compound containing 47.9% potassium, 5.5% beryllium and 46.6% fluorine by mass.
(Atomic weight of K=39, Be=9, F=19).     


4- MARKS QUESTIONS 

1) 80 cm³ of methane is mixed with the 200 cm³ of pure oxygen at room temperature and pressure. The mixture is then ignited when it burns as illustrated by equation. Calculate the composition of resulting mixture. if it is cooled to initial room temperature and pressure.
CH₄(g)+ 2O₂(g)---> CO₂(g)+ 2H₂O(l).      

2)  200cm³ CO₂ is collected at STP when a mixture of acetylene and oxygen is ignited. Calculate the volumes of acetylene and oxygen at STP in original mixture.
2C₂H₂ + 5O₂ ---> 4CO₂ + 2H₂O. 

3) a) Iron pyrite has a formula FeS₂. What mass of Sulphur is contained in 30g of iron pyrite ?
b) When roasted, iron pyrite gives Sulphur dioxide according to the following equation:
4FeS₂ + 11O₂ ---> 2Fe₂O₃ + 8SO₂ 
What volume of Sulphur dioxide (at STP) would be liberated by the roasting 30 g of iron pyrite ?
(Fe=56, S=32, ;  molar volume of a gas is 22.4 l at STP).   

4) What volume of oxygen is required to burn completely a mixture of 22.4 dm³ of Methane and 11.2 dm³ of hydrogen into carbon dioxide and steam?
Equation of the reactions are given below. ( Assume that all volumes are measured at STP)
CH₄ + 2O₂ ---> CO₂ + 2H₂O
2H₂ + O₂ ---> 2H₂O.       





6/12/24

1) In quadrilateral ABCD, angle D=90°,
 BC= 38cm and DC= 25 cm. A circle inscribed in this quadrilateral which touches AB at a point Q such that QB= 27cm. Find the radius of the circle.    

2) Two circles of radii 18cm and 8cm touch externally. Find the length of a direct common tangent to the two circles.     

3) Two parallel tangents of a circle meet a third term at P and Q.
Prove that PQ subtends a right angle at the centre.

4) In the figure,
a circle touches the side BC of ∆ ABC at P and AB and AC produced at Q and R respectivelly. Prove that AQ = AR= (1/2) (perimeter of ∆ ABC ).

5) P and Q are centres of circles of radius 9cm and 2cm respectively. PQ = 17cm. R is the centre of a cycle of x cm, which touches the above circles externally. Given that angle PRQ - 90°, write an equation in x and solve it.     

6) Find the length of the tangent drawn to a circle radius 4cm from a point 5cm away from the centre of the circle.      

7) In the figure,
A, B and C are 3 points on a circle, The tangent at C meets BA produced at T.  Given that angle ATC= 36° and angle ACT= 48°, Calculate the angle subtended by AB at the centre of the circle.    

8) In the figure,
XY is a diameter of the circle, PQ is a tangent to the circle at Y. Given that angle AXB= 50° and angle ABX= 70°,  calculate 
a) angle BAY.    
b) angle APY.    

9) In the figure,
O is the centre of the circumcircle of ∆ XYZ. Tangents at X and Y intersect at T. Given angle XTY= 80° and angle XOZ= 140°,  calculate the value of angle ZXY.        
R-2

1) The radius of a circle with centre O is 9cm. A point is at a distance of 41cm from O. Find the length of the tangent from P to the circle.     

2) A point A is 26cm away from the centre of the circle and the length of tangent drawn from A to the circle is 24cm. Find the radius of the circle.     

3) The radius of a circle is 8cm. The length of the tangent drawn from an exterior point P to the circle is 15cm. Find the distance of the point P from the centre of the circle.    

4) Two circles of radii 3cm and 5cm are concentric. Calculate the length of a chord of the outer circle which touches the inner circle.      

5) Three circles with centres A, B and C and radii 3.3cm, 4.2cm and 4.6cm respectively touch each other externally. Find the length of the sides of ∆ ABC.

6) Three circles with centre X, Y and Z touch each other externally. If XY = 6cm, YZ= 9cm and XZ= 7.5 cm, find the radius of the circles.     

7) A and B are centres of circles of radii 9cm and 2cm such that AB=17cm and C is the centre of the circle of radius r cm, which touches the above circles externally. If Angle ACB= 90°, write an equation in r and solve it.      

8) Two circles of radii 25cm and 9cm touch each other externally. Find the length of the direct common tangent.     

9)  Two circle of radii 6cm and 14cm have their centres 30cm apart. Find the radius of the smallest circle that can be drawn to touch them and encloses the smaller.    

10) The length of the direct common tangent to two circles of radii 8cm and 6cm is 15cm. Calculate the distance between their centres.     

11) PQRS is a square of side 12cm. A circle with centre P and radius 4cm is drawn. Another circle is drawn touching RS at R and the first circle. Find the radius of the second circle.    

12) In the figure,
ABC is a right angled triangle with AB= 12cm, BC= 5cm. A circle with centre O has been inscribed inside the triangle. Calculate the value of x, the radius of the inscribed circle.     

13) In figure,
the incircle of ∆ ABC touches the sides AB, BC and AC at the point P,Q,R  respectively. Prove that:
AP+ BQ+ CR= BP + CQ + AR = (1/2) (Perimeter of ∆ ABC)

14) A circle touches the side AB, BC, CD and DA of a quadrilateral ABCD at P, Q, R and S. Given that AP= 2cm, BP = 3.2cm, DR= 2.5cm and CQ= 4.3cm. Calculate the perimeter of ABCD .      

15) A circle touches the sides of a ∆ PQR at A, B , C. If A, B are the midpoints of PQ, QR respectively. Prove that C is the mid point of PR.

16) In the figure,
PA and PB are tangents to the circle with centre O and ∆ ABC has been inscribed in the circle such that AB= AC. If Angle BAC= 72°,  Calculate 
a) angle AOB.    
b) angle APB.     

17) In the figure,
all the sides of a quadrilateral PQRS touch a circle with Centre O. Prove that angle POQ+ angle ROS = 180° and angle QOR+ POS =180°.

18) In the figure,
the sides of a quadrilateral touch the circle. Prove that PQ+ RS= QR+ SP.

19) Two circles touch each other externally . Prove that the lengths of tangent drawn to the circles from any point on the common tangent are equal.

20) In the figure,
PQ is a diameter of the circle with Centre O and QT is a tangent. Find the value of angle QTR. 

21) Show that the line segment joining the points of contact of two parallel tangents to a circle passes through the centre.

22) Show that the tangent lines at the end of the points of a diameter of a circle are parallel.

23) Prove that the Tangents at the extremities of any chord make equal angles with the chord.

24) In the figure,
two circles touch each other externally at point P. AB is the direct common tangent to these circles . Prove that:
a) The tangent at P bisects AB.
b) angle APB= 90°

25) In the figure,
TP and TQ are tangents to the circle with centre O from an exterior point T. Show that angle PTQ= 2 angle OPQ.




4/12/24
1) (1- sin²A) sec²A = 1.

2) (1+ tan²A) cos²A = 1.

3) (cosec²A -1) tan²A= 1.

4) tan²A - sin²A = tan²A. sin²A.

5) 1/(secx + tanx) = (1- sinx)/cosx.

6) 1/(secx - tanx) = secx + tanx.

7) sinx/(1- cosx) = cosecx + cotx.

8) sin²x cot²x + cos²x tan²x = 1.

9) (1- sinx)/(1+ sinx)= (secx - tanx)².

10) cot²x - 1/sin²x = -1.

11) (secx -1)/(secx +1)= (1- cosx)/(1+ cosx).

12) sec²x + cosec²x = sec²x cosec²x.

13) cotx - tanx = (2cos²x -1)/(sinx cosx).

14) (1- cosx)(1+ cosx)(1+ cot²x)= 1.

15) cosx/(1+ sinx)= (1- sinx)/cosx.

16) sinx(1+ tanx)+ cosx(1+ cotx)= secx + cosecx.

17) (secx + cosx)(secx - cosx)= tan²x + sin²x.

18) (sinx - cosx)(cosx - secx)(tanx + cotx)= 1.

19) tanx + cotx = secx cosecx.

20) 1/(1+ sinx) + 1/(1- sinx)= 2 sec²x.

21) (1+ sinx)/cosx + cosx/(1+ sinx)= 2 secx.

22) 1/(cosecx - cotx)= cosecx + cotx.

23) (cosecx + cotx)= (cosecx + cotx)²= 1+ 2 cot²x + 2 cosecx cotx.

24) (secx + tanx)/(secx - tanx)= (secx + tanx)²= 1 + 2 tan²x + 2 secx tanx.

25) sec²x + cosec²x = sec²x cosec²x.

26) sinx/(1+ cosx) + (1+ cosx)/sinx = 2 cosecx.

27) cosecx/(cosecx -1) - cosecx/(cosecx +1)= 2 sec²x.

28) cosx/(1- tanx) - sin²x/(cosx - sinx)= cosx + sinx.

29) cos²x/sinx + sinx = cosec x.

30) tan²x + cot²x + 2 = sec²x cosec²x.

31) (1- tan²x)/(cot²x -1) = tan²x,

32) (1- cosx)/(1+ cosx)= (cotx - cosecx)².

33) √(sec²x + cosec²x)= tanx + cotx.

34) (1+ cotx - cosecx)(1+ tanx + secx)= 2.

35) (tanx + secx -1)/(tanx - secx +1)= (1+ sinx)/cosx.

36) (1+ cosx + sinx)/(1+ cosx - sinx)= (1+ sinx)/cosx.

37) √{(1+ sinx)/(1- sinx)}= cosx/(1- sinx).

38) √{(1+ cosx)/(1- cosx)} = sinx/(1- cosx).

39) √{(1- cosx)/(1+ cosx)} = cosecx - cotx.

40) (1+ tan²x)cotx/cosec²x = tanx.

41) (tanx + sinx)/(tanx - sinx)= (secx +1)/(secx -1)

42) {(1+ sin²x)+(1- sinx)²}/2cos²x = (1+ sin²x)/(1- sin²x).

43) (1+ tan²x)/(1+ cot²x)= {(1- tanx)/(1- cotx)}².

44) 1/(cosecx + cotx) - 1/sinx = 1/sinx - 1/(cosecx - cotx).

45) 1/(secx + tanx) - 1/cosx = 1/cosx - 1/(secx - tanx).

46) (sinx + cosx)/(sinx - cosx) + (sinx - cosx)/(sinx + cosx)= 2/(sin²x - cos²x).

47) sin²x cos²y - cos²x sin²y = sin²x - sin²y.

48) (tanx + tany)/(cotx + city)= tanx tany.

49) sec⁴x - sec²x = tan⁴x + tan²x.

50) (sin⁸x - cos⁸x)= (sin²x - cos²x)(1- 2 sin²x cos²x).

51) sin²x cos²y + cos²x sin²y + cos²x cos²y + sin²x sin²y = 1.

52) (sinx + cosx)(1- sinx cosx)= = sin³x + cos³x.

53) (1- cos²x)cosec²x = 1

54) (1+ cot²x) sin²x = 1.

55) (sec²- 1) cot²x = 1.

56) (tanx + sinx)/(tanx - sinx)= (secx +1)/(secx -1).

57) (1+ sinx)/cosx + cosx/(1+ sinx)= 2 secx.

58) (secx - tanx)²= (1- sinx)/(1+ sinx).

59) (1+ tan²x)(1- sinx)(1+ sinx)= 1.

60) (secx -1)/(secx +1)= (1- cosx)/(1+ cosx).

61) sec²x + cosec²x = sec²x cosec²x.

62) (1+ secx)/secx = sin²x/(1- cosx).

63) cotx - tanx = (2cos²x -1)/(sinx cosx).

64) secx(1- sinx)(secx + tanx)= 1.

65) √{(1+ sinx)/(1- sinx)}= secx + tanx.

66) √(cot²x - cos²x)= cotx cosx.

67) (secx + cosecx)(sinx + cosx)= 2+ secx cosecx.

68) tan²x - tan²y = (sin²x - sin²y)/(cos²x cos²y).

69) sin⁴x - cos⁴x = 1- 2 cos²x.

70) cos⁴x + sin⁴x + 2 sin²x cos²x = 1.

71) cos⁴+ sin⁴x - 2 sin²x cos²x = 1- 4 sin²x cos²x.

72) 2(sin⁶x + cos⁶x) - 3(sin⁴x + cos⁴x)+ 1= 0.





4/12/24
1) The diagram shows
a point source of light S, a convex lens L and a plane mirror M.  The three are placed in such that the ray of light from S return to it after reflection from M.
a) What is the distance OS called ?
b) To which point (left of S, on S or right of S) will the rays return if M is moved to the left and is brought in contact with L ? 

2) Two isosceles right angled prism are arranged as shown in the figure.
Copy the diagram and complete the path of the rays AB along which it passes through the prisms and come out.
 Name the phenomena being displayed by the path of ray in given diagram.

3) After a robbery , if a window has been broken, there will be tiny particles of glass. Some of these will be found at the scene of the crime and some maybe caught in the thief's clothing. If the police can prove that these particles are identical, they have a strong case.    
   A method of doing this is to suspend the particles of glass in a special liquid. Light of a single colour is shone through the liquid and the particles viewed through a microscope. The temperature of the liquid is then slowly altered. This alters the speed of light through the liquid (i.e., it alters the refractive index). At one particular temperature the particles of glass disappear. If this happens at the same temperature for both sets of glass particles, They probably came from the same broken pane of glass.
a) Complete a copy of the diagram to show how light bends when it travels from the liquid to the glass and back to the liquid.
i) if the light close down in the glass.
ii) if the light speeds up in the glass.
b) Why is the light used in the police work in a single colour ?
c) Under what two circumstances can light moving from a liquid to glass pass straight on without bending ?
d) When do the particles of glass disappear in the police method ?

4) Copy the diagram below and complete the ray diagram to show the nature of light produced on the screen.

 
5) a) Complete the following diagram indicating the focal lengths of the lenses. 
b) Two bodies have their masses in the ratio 3:4 are acted upon by same force. Compare their accelerations.

6) The crow bar is a type of a lever as shown below:
A crow bar of length 150 cm has its fulcrum at a distance of 25cm from the load. Calculate the mechanical advantage of the crowbar.


7) The critical angle for the glass of which the equilateral prism ABC is made, is 48°, A ray of light incident on the side AB of the prism is refracted along DE such that the angle it makes with the side AC is 138°,  Also, angle EDB= 90°. Copy the diagram.
a) Draw the path of the ray incident on the side AB (which travels along DE)
b) Show the path along which the ray DE travels from the point E onwards and through the side BC.

8) The diagram
shows the use of a lever .
i) State the principle of moment as applied to the above lever.
ii) Given an example of this class of lever.
iii) if FA=10cm; AB= 500cm, calculate the minimum effort required to lift the load.

9) a) The graph represents cooling curve for a substance being cooled from a higher temperature to a lower temperature.
i) What is the boiling point of the substance.
ii) What happens in the region DE.
iii) Why is the region DE is shorter than the reason BC.
b) At what approximation temperature will water boil in a pressure cooker ?

10) The given diagram below shows a ray of white light AO incident on a rectangular glass block, which is silvered  at one surface. This ray is partly reflected and partly refracted.
a) Copy the diagram and trace the path of the refracted and reflected ray. Show at least two rays emerging out from surface PQ.
b) How many images are formed in the above case? Which image is the bright?
    
11) The diagram shows a student's vision for his near point.
a) What defect is he suffering from ?
b) State one cause for occurrence of this defect.
c) Copy the diagram and complete it to be show how this defect is corrected.

12) The following diagram shows two straight wires carrying current. Copy the diagram and draw the pattern o lines of force around them and mark their directions.


13) The diagram shows a system 5 pulleys.
a) Copy the diagram and complete it by drawing a string around the pulleys. Mark the position of the load and the effort.
b) if the load is raised by 1m, through what distance will the effort move ?

14) Two musical notes of same pitch and loudness are played on a violin and a piano. Their waveforms are shown in figure below.
Explain why the wave patterns are different.

15) Diagram below shows a weightless lever in equilibrium. Neglect friction at the fulcrum F.
a) State the principle of the moments as applied to the above lever.
b) Define mechanical advantage and calculate its the value for the given lever.
c) Name the type of lever which has mechanical advantage greater than 1.

16) Diagram below shows an object AB placed on the principle axis of a convex lens placed in air. F₁ and F₂ are the two focii of the lens.a) Draw a ray of light starting from B and passing through O. Show the same ray after refraction by the lens.
b) Draw another ray from B which passes through F₂ after refraction by the lens.
c) Locate the final image formed.
d) Is the image real or virtual.

17) diagram below shows a circuit containing a coil wound on a long and thin hollow cardboard tube. Copy the diagram.
a) Show the polarity acquired by each face of the solenoid.
b) draw the magnetic lines of force inside the coil and also show their directions.
c) mention two methods to increase the strength of the magnetic field inside the coil.

18)  Diagram below gives an arrangement of single moving pulleys 
copy the diagram. if the effort applied at the free end of the string is E.
a) Show the direction and magnitude of the forces exerted by the four springs marked 1- 4
b) What is the load which can be lifted by the effort ?
c) Calculate the mechanical advantage of the system of pulleys .

     










2/12/24
1) A hot solid of mass 60g at 100°C is placed in 100g of water at 18°C. The final steady temperature recorded is 20°C. Find the specific heat capacity of the solid.    

2) Calculate the electrical energy in SI unit consumed by a 100W bulb and 60W fan connected in parallel for 5 minutes.     

3) Calculate the mass of steam at 100°C that must be passed into 8.4kg of water at 30°C to raise the temperature of water to 80°C. Specific heat capacity of water = 4.2 j/g°C and specific latent heat of vaporization of steam = 2268 j/g.  

4) In the figure shown,
Calculate 
i) the value of combined resistance of 40ohm and R, using the reading of the two metres.    
ii) The value of R.    
iii) The current flowing through R.   

5) How much does it cost to run one heater of 1000W and two electric bulbs of 40 W each of 8 hours if one unit of electricity cost Rs2.      

6) In an experiment to measure the specific heat capacity of brass 0.2kg of hot water, at a temperature 65°C, was poured into a heavy brass container of mass 1.5 kg, initially at 15°C.  After stirring , the final temperature reached was 45°C. Assume that the specific heat capacity of water is 4200 j/kg/°C.
a) Calculate the heat energy released by the hot water in cooling from 65°C to 45°C.      
b) Assume that the heat energy calculated in part (a) is gained by the brass container in raising its temperature from 15°C to final common temperature of 45°C. Calculate the hat energy abserbed by the brass container per °C rise in temperature.     
c) Using the result obtained in part (b). Calculate the specific heat capacity of brass.     

7) A  Lens has a power of +5 D.
a) What is its focal length ?      
b) What is the nature of the lens.       

8) Calculate the length of a wire of 20 Ω and area cross section 0.2 cm² in SI. Specific resistance of a wire is 8 x 10⁻⁶ ohm-m.        

9) An electric oven is rated 2000 W. If the resistance of the element is 50 Ω, find 
a) potential difference at which it operates ?      316.2 Volts
b) Monthly bill, if is used for 2 hours a day and electric energy costs Rs2 per kWh. Take 1 month = 30 days.    

10) Steam at 100°C is passed over 1000g of ice at 0°C. After some time, 600g of ice at 0°C is left and 450g of water at 0°C is formed. Calculate the specific latent heat of vaporization of steam. ( given: specific heat of water =4200 J/kg°C and specific latent heat of fusion of ice= 336000 J/kg).         

11) The figure shows 
a battery having an e.m.f of 9V and internal resistance R= 0.6 Ω, connected to 3 resistors A, B and C. Calculate the current in each resistor.    

12) A cell of e.m.f of 2 volts and internal resistance 1ohm is connected with two wires of resistances 2 and 5 ohm in parallel. Find the current in each wire.    

13) The amount of heat required to convert 1 kg of ice at -10°C to steam at 100°C is 3037000 J.  Calculate the latent heat of vaporization of steam.
 given: (specific heat capacity of ice= 2100 J/kg K; specific heat capacity of water= 4200 J/kg K; specific latent heat capacity of ice = 336000 J/kg).    

14) In the figure given below,
calculate the resistance between the point
a)  X and Y
b) A and B. 


13/11/24

ORGANIC CHEMISTRY 

Answer the following 

1) What is spurious alcohol ?

2) Why do organic compounds have usually low melting and boiling points ?

3) Methane is used as a gaseous fuel. Why ?

4) What is Power alcohol ?

5) Write the structural formula propene .

6) Give the structural formula of n-butane.

7) Give the structural formula of propionatealdehyde

8) Give the structural formula of ethanoic acid.

9) What are isomers?

10) How do the physical and chemical properties of isomers different?

11) Write the molecular formula of the third member of the homologous series of the carbon compounds with the general formula CₙH₂ₙ₊₁OH.

12) A test tube contents a brown coloured liquid in it. The colour of the liquid remains unchanged when the methane is passed through it. But it disappears when ethene is passed. Suggest the name of the substance giving brown colour to the liquid.

13) Write the molecular formulae of the third and the fifth members of the homologous series of carbon compounds represented by CₙH₂ₙ₊₂.

14) Why does the acetylene burn with sooty flame ?

15) Write the chemical equation for the reaction which takes place during the burning of ethanol in air.

16) A compound has molecular formula C₂H₆O. It is usable as a fuel. Identify the compound.

17) What do you mean by olefins ?

18) Which of the following compounds contain a carboxyl group ?
CH₃OH, CH₃COOH, CH₃CHP, CH₃COCH₃.

19) which of the following compounds can have a double bond ?
C₃H₄ , C₃H₆, C₃H₈ 

20) What happens when a mixture of Sodium acetate and soda lime is heated?

21) What happens when methane gas is burnt in air?

22) What happens when the ethene reacts hydrogen chloride ?

23) What happens when ethanol reacts with oxygen ?

24) What happens when acetic acid and ethanol react in the presence of concentrated sulphuric acid ?

25) The alkenes having how many carbon atoms are in solid at normal temperature ?

26) The alkenes having how many carbon atoms are in liquid state at normal temperature.

27) By which type of flame does ethene gas burn in air ?.

28) By which type of film does acetylene gas burns in the air ?

29) What is structural isomerism ?

30) What are hydrocarbons ?

31) What are saturated hydrocarbons?

32) Give the chemical equation for the following reaction:
Vapours of methanol and carbon monoxide gas are passed over catalytic iodine-rhodium.

33) What is meant by decarboxylation ?

34) What word is used to describe three compounds taken together ?

35) Write the equation of the laboratory preparation of ethyne (acetylene) from calcium carbide.

36) What is the special feature of the structure of ethyne?

37) What would you see when ethyne is bubbled through a solution of bromine in carbon tetrachloride ?

38) Write the balanced equation for the following reaction:
Ethene and hydrogen.

39) State what do you observe when the ethene is bubbled through a solution of bromine is tetrachloromethane (carbon tetrachloride).

40) Write a balanced equation for the complete combustion of ethane.

41) Ethyne forms an addition product with the chlorine. Name this addition product and write its structural formula.

42) Write balanced equation for the following reaction:
Ethane is burnt in air.

43) Give the balance equation for the following reaction : Formaldehyde and oxygen.

44) Match the description below with the appropriate time from the list A to J;
A. Acid oxide B. Alkali C. Amphoteric oxide D) basic oxide E. Deliquescene E. Efflorescence G. Electrolysis H. Electrolye I. Homologous series  J. Hydrocarbons 
A set of compounds having the same general formula, similar methods of preparation and similar chemical properties.

45) Define the term catenation.


B) Fill in the blanks by choosing the correct word/s given within the brackets.

1) Compound having the same molecular formula but having different structural formula are called____( homologous /isomers)

2) Organic compounds are____ compounds(ionic/covalent)

3) The organic compounds containing carbon and____ atoms only are called hydrocarbons. (oxygen/hydrogen)

4) Organic compounds are generally insoluble in ___(organic solvents/ water)

5) C= C bond is___ than C --C bond. (longer/shorter)

6) An alkyl group is formed by removing a___ atom from the parent alkane.   (carbon/ hydrogen)

7) Ethanol containing some methanol added to it is called ____ alcohol.   (Ethylated/ methylated)

8) The next higher homologous of methanal is____.    (propanal/ethanal)

9) The conversion of ethanol to ethene is an example of _____.   (dehydration/ dehydrogenation)

10) Converting ethanol to ethene requires the use of___.   ( concentrated hydrochloric acid/concentrated nitric acid/ concentrated sulphuric acid)

11) The conversion of ethene to ethane is an example of____.    (hydration/hydrogenation )

12) The catalyst using in the conversion of ethene to ethane is commonly___.   (Iron/Cobalt/nickel )




C) Name the following :

1) Two alcoholic beverages obtained only by fermentation.

2) The first four members of the homologous series of alkanes.

3) The first four members of homologous series of alkynes.

4) The first four members of homologous series of alkenes.

5) The products obtained when ethanol :
     a) reacts with excess of concentrated H₂SO₄.
     b) burns completely in air.

6) The hydrocarbon used for artificial ripening of fruits.

7) A compound used in making denatured alcohol.

8) The  IUPAC names of ethyl alcohol and acetic acid.

9) The functional groups present in the following compounds:
     a) CH₃COOH
     b) CH₃CH₂OH

10) Compounds having the same molecular formula but different chemical and physical properties.

11) The isomers of Butane 

12) The isomers of pentane 

13) The gas obtained by pouring cold water on calcium carbide.

14) The name aychemical formula of the simplest alkyne.

15) The chemical name of the gas which evolves in the marshy lands in the form of bubbles.

16) The name and the physical formula of the simplest organic acid.

17) The property of self linking of carbon atoms through covalent bonds.

18) Minimum number of carbon atoms for two isomers of a hydrocarbon.

19) The prefix used for those organic compounds in which at least one carbon atom is attached to three other carbon atoms.

20) The physical state of an alkane having eight carbon atoms per molecule.

21) The thermal decomposition of alkanes in the absence of air at a high temperature.

22) Products formed when methanal reacts with concentrated sodium hydroxide solution.

23) Aqueous solution of formaldehyde.

24) The addition product former between the ethene and water.

25)  a compound formed by dehydration of ethanol by concentrated sulphuric acid.

26) a compound which has vapour density 14 and turns alkaline potassium dichromate green .

27) a compound which decolourizes bromine solution in carbon tetrachloride.

28) A carbon which will give red precipitate with ammoniacal cupurous chloride solution.

29) a compound which forms chloroform on halogenation in the presence of sunlight.

30) a compound which forms methanoic acid on oxidation in the presence of copper at 200°C.

31) A reagent which can be used to distinguish between ethane and ethene.

32) A liquid which is non-electrolyte.

33) a solid which can be used instead of concentrated sulphuric acid to prepare Ethylene by the dehydration of ethanol.

34) From the given list, name:
    Ethane, ethene, ethanoic acid, ethyne, ethanol.
    i) The compound with ---OH as the part of its structure.
   ii) the compound with --- COOH as the part of its structure.
   iii) Homologue of Homologous series with general formula CₙH₂ₙ



D) State whether true or false:

1) The IUPAC names of various classes of the organic compounds are derived from alkenes.

2) C- C bond is longer than C= C bond 

3) acetylene is a tetrahedral molecule.

4) isomerism is the phenomenon when different compounds have the same molecular formula.

5) organic compounds contain ionic linkage.

6) ethanoic acid cannot be used as a laboratory reagent.

7) Methanol causes an irritation in eyes.


 

E) Write true or false for the following sentences . also correct the false statements.

1) Addition reactions are characteristic of ethane, while substitution reaction for ethene.

2) ethylene is more reactive than acetylene , while ethylene is less reactive than ethane.

3) ethyne is comparatively less reactive than ethene.

4)  spurious alcohol is unfit for human consumption.

5) A carbon atom is able to form two single bonds by sharing electrons with neighbouring atoms.

6) formaldehyde is different from other members aldehyde family.

7) acetic Acid turns red litmus blue.




F) Choose the correct answer from the choices 

1) Which one of the following is the formula of an organic compound ?
a) NaCl b) CH₄ c) NH₃ d) SO₂ 

2) Which one of these gases burns in oxygen to form carbon dioxide and water vapour and also decolourizes bromin water ?
a) CH₄ b) C₂H₆ c) C₂H₄  d) CO

3) Which one of the following is the structural formula of an alkaline ?
a) H₃C---CH₂--CH₂--CH₃
b) H₃C--CH₂--OH
c)       O
           ||
CH₃----C---OH
d) H₂C = CH₂

4) Which of the following is a colourless and odourless gas ?
a) Ethan b) ethyne  c) Methane  d) methanol

5) Which of the following is known as wood alcohol ?
a) C₂H₄ b) C₂H₂ c) CH₃OH d) C₂H₆OH


EACH QUESTION CARRIES 2 MARKS 

1) What is isomerism ? What are its types ?

2) On heating soda lime with Sodium acetate, a colourless gas 'G' is produced. This gas is lighter than air.
a) Name the gas G.
b) The gas burns into a blue flame in excess of oxygen. Write the chemical equation for it.

3) Why is it dangerous to burn methane in an insufficient supply of oxygen ? Write the chemical equation for the reaction.

4) a) How is ethene prepared ?
b) How is it collected ?

5) What happens when ethene reacts with bromine?

6) Give reactions :
a) Addition of ethene with halogen (for example, Br₂)
b) Addition of ethene with hydrogen.

7) Write any two uses of ethene.

8) Give the common name of the class of compounds having the general formula CₙH₂ₙ₋₂. Write the name of the first member of this homologous series.

9) Which of the following compounds will give addition reactions ?
C₂H₆ , C₃H₈ , C₂H₄ , CH₄ , C₄H₁₀ , C₅H₈
give reason for your answer.

10)  A compound is formed by the substitution of two chlorine atoms for two hydrogen atoms in propane. What is the number of structural isomers possible ? Name them.

11) An organic compound 'X' which is sometimes used as antifreeze has the molecular formula C₂H₆O. On addition it gives a compound Y which gives effervescence with baking soda solution. What can X and Y be ?

12) State any four uses of alcohol(ethanol) in daily life.

13) a) what are aldehyde ?
b) how is formaldehyde different from other members of aldehyde family ?.

14) Why are aldehydes called carbonyl compounds.

15) Why is ethanoic acid called glacial acetic acid?

16) Give chemical equations for the following reactions :
a) ethanoic acid reacts with zinc 
b) reduction of formaldehyde

17) By which name 40% aqueous solution of methanol is known ? Give its two uses.

18) a) Write the general formula of the carboxylic acids .
b) Give the common name and IUPAC names of CH₃COOH.

19) Ethane and chlorine react together to form monochloroethane (ethyl chloride).
a)  Write down the structural of formula of ethane.
b) what type of reaction has taken place between ethane and chlorine ?

20) Write the structural formula of marsh gas.

21) Copy and complete the following sentence.
A saturated hydrocarbon will undergo _____reaction whereas the (typical reaction of an unsaturated hydrocarbon is ).

22) Write the names and structural formula of :
a) a saturated hydrocarbon 
b) an unsaturated hydrocarbon with a double bond 

23) Write the equations for the following laboratory preparation:
a)  ethane from sodium propionate.
b) ethyne from calcium carbide.

24) a) Which compound should be heated with soda land to obtain ethane gas in the laboratory ?
b) Write the equation for the reactions in (a) above .


EACH QUESTION CARRIES 3 MARKS

1) Differentiate between organic and inorganic compounds

2) Differentiate between Saturated and unsaturated hydrocarbons.

3) Give molecular and structural formula of the following:
a) propane 
b) butane 
c) ethane 

4) Write general formula for the following:
a) Alkanes
b) Alkenes 
c) Alkynes

5) Which of the following are alkanes, alkenes and alkynes
C₂H₂ , C₂H₈ , C₂H₄ , C₃H₈

6) state three characteristics of Isomers .

7) A hydrocarbon A is obtained by the cracking kerosine 
a) identify the hydrocarbon.
b) what happens when it reacts with bromine water 
c) write the chemical equation for the reaction.

8) You are provided with three jars containing methane, ethene and ethyne respectively. What tests will you carry out to distinguish them ? Explain.

9) An organic compounds A is a constituent of wine and beer. This compound on heating with potassium dichromate or oxygen forms another organic compound B.
a) Identify the compound A
b) write the chemical equation for the reaction that takes place to form the compound B
b) name the compound B

10) what are alkyle radicals and how are the named?

 



   




TEST PAPER - 1(Chemistry)


Section I (40 Marks)
Attempt all questions from this Section 

Question 1.
a) At room temperature and pressure, one mole of Sulphur dioxide occupies 24 dm³.
i) What is the mass of 6 dm³ of Sulphur dioxide at the same temperature and pressure ?
ii) What is the volume occupied by 80g of Sulphur dioxide at the same temperature and pressure ?
iii)  How many moles of Sulphur dioxide represent in 96 kg of it ?
iv) if one mole of Sulphur dioxide contains N molecules, how many molecules are there in 0.64g of sulphur dioxide?
v) Calculate the weight of 0.5 g molecules of sulphur dioxide. (S= 32, O= 16).   (5)

b) Choose the correct answer from the choices A, B, C, D.
i) Which of the following is an unsaturated compound ?
A) C₆H₁₄ B) C₃H₇OH C) CH₃OH D) C₄H₈

ii) Which of the following contains maximum number of molecules ?
A) 4g of O₂ b) 4g of NH₃ c) 4g of SO₂ d) 4g of CO₂ 

iii) On moving from left to right in a period, the metallic characters of elements:
A) increases B) decreases C) remains the same D) varies where irregularily

iv) The ions present at the anode during the electrolysis of molten lead bromide are:
A) Pb²⁺ions B) Br²⁻ ions C) Br⁻ ions D) none 

v) Which of the following has the highest electron affinity ?
A) F⁻ B) O C) O⁻  D) Na⁺ 


c) i) Explain why electrolysis takes place in aqueous solution or molten state ?
ii) Why is it necessary to add acid to water before proceeding with the electrolysis of water ?
iii) Name a substance which when dissolved in water contains both ions and molecules.
iv) Write the equations for the reactions which takes place at the electrodes during the electrolysis of lead bromide.      (5)

d) Both sulphur dioxide and chlorine are used as bleaching agents.    (5)
i) Explain the bleaching action of Sulphur dioxide with the help of chemical equations .
ii) Give a reason why chlorine is not used in bleach silk.
iii) Why is bleaching by Sulphur dioxide only temporary ?
iv) State the similarity in the use of Sulphur dioxide and chlorine as bleaching agents. 


e) Name the following. Choose the right words from the box.
(Efflorescent substance, pyrolysis, hydracid, cathode, anode, oxyacid, carbon, bromin )
i) A nonmetallic element which forms acidic and neutral oxides.
ii) The electrode connected to the negative terminal of the battery during electrolysis.
iii) A substance which loses its water of crystallization when exposed to open air.
iv) An Acid which lacks oxygen in its composition.
v) The process of thermal decomposition of alkanes in the absence of air at high temperature.     (5)

f) Write balanced equations for the following reactions:
i) Copper hydroxide and dilute nitric acid.
ii) Ammonium sulphate and calcium hydroxide.
iii) Aluminium oxide and Sodium hydroxide.
iv) zinc oxide and sodium hydroxide.
v) Lead(IV ) oxide and concentric hydrochloric acid.

g) The following questions relate to the extraction of aluminium.   (5)
i) What is the significance of cryolite ? Give its chemical formula.
ii) Powdered coke is sprinkled over the electrolytic mixture. Why ?
iii) Name three positive ions formed during the electrolytic reduction of alumina.
iv) During the whole process of extraction of aluminium by electrolysis, a low voltage current is used. Why ?
v) Write the equation for the action of heat on aluminium hydroxide.

h) The question(i) to (v) refer to the following salt solution listed A to F:
A)  Copper nitrate B) Iron sulphate C) Iron(III ) chloride D) Lead nitrate  E) magnesium sulphate  F) zinc chloride 
i) Which two solutions will give a white percipitate when treated with dilute hydrochloric acid followed by barium Chloride solution ?
ii) Which two solutions will give a white precipitate when treated with dilute nitric acid followed by Silver Nitrate solution ?
iii) Which solution will give a white precipitate when either dilute hydrochloric acid or dilute sulphuric acid is added to it ?
iv) Which solution becomes a deep/ inky blue colour when excess of Ammonium hydroxide is added to it ?
v) Which solution gives a white precipitate with excess Ammonia hydroxide solution ?


SECTION II (40 Marks)
(Attempt any four  questions from this Section)

Question 2.
a) Write the equation for the following reactions .     (4)
i) Dilute nitric acid producing carbon dioxide.
ii) Dilute sulphuric acid producing hydrogen.
iii) Between Copper and concentrated nitric acid.
iv) Between lead nitrate solution and dilute sulphuric acid.

b) i) Write the equation for the following reactions which result in the formation of ammonia:
      1. A mixture of ammonium chloride and slaked lime is heated.
      2. Aluminium nitride and water.
ii) Calculate the percentage of water crystallization in a washing soda crystal. (H=1, C= 12, Na= 23, O= 16).        (4)


c)i) Classify the solutions of the following as acids , bases or salts:    (2)
Ammonium hydroxide, barium Chloride, sodium chloride, Sodium hydroxide. H₂SO₄, and HNO₃.
ii) Explain how a reagent chosen from those in (c)(i) enables you to distinguish between the two acids mentioned there in:

Question 3
a) From the equation: (NH₄)₂ Cr₂O₇ ---> Cr₂O₃+ 4H₂O + N₂ 
Calculate :
i) the volume of the nitrogen at STP evolved when 63g ammonium dichromatic is heated.
ii) the mass of the chromium(III ) oxide, Cr₂O₃ formed at the same time.
(N=14, H=1, Cr= 52, O= 16)


b) The reaction 4N₂O+ CH₄--> CO₂+ 2H₂O+ 4N₂ takes place in the gaseous state. If all volumes are measured at the same temperature and pressure. Calculate the volume of dinitrogen oxide (N₂O) required to give 150 cm³ of steam. (N=14, O=16, C= 12, H= 1).  (2)

c) A gaseous hydrocarbon contains 82.6% carbon. If the vapour density of the hydrogen is 29. calculate its molecular formula. Also write two possible structural formula of the hydrocarbon.     (4)

Question 4
a) i) which feature of the ammonium molecules leads to formation of the Ammonium ions when Ammonia dissolves in water ?
ii) Name the other ion formed when Ammonia dissolves in water.
iii) Give one test that can be used to detect the presence of the ion produced in (ii).  (3)

b) From the metals copper, iron, magnesium, sodium and zinc, select a different metal in each case which :
i) does not react with dilute hydrochloric acid.
ii) can form 2⁺ and 3⁺ ions
iii) has hydroxide that reacts with both acids and alkalis.
iv) does not react with cold water but reacts with steam when heated.   (4)

c) Choosing only substances from the list given in the box below, write equations for the reactions which you would use in the laboratory to obtain:
i) sodium sulphate 
ii) iron sulphate
iii) zinc carbonate      (3)
(dilute sulphuric acid,  iron,  copper carbonate, sodium sodium carbonate, zinc)

Question 5
a) Differentiate between the chemical nature of an aqueous solution of hydrogen Chloride and an aqueous solution of Ammonia .

b) The figure given below illustrates the apertures used in the catalytic oxidation of ammonia.
i) Name A, B, C and D.
ii) Write the equation to show the catalytic oxidation of ammonia.
iii) The catalyst used in the process continuous to glow even after the heating is stopped. Why?    (4)

c) Write the equation for:
i) the preparation of the ammonia from ammonium chloride and Calcium hydroxide.
ii) the preparation of hydrogen chloride from the sodium chloride and Sulphuric Acid. State whether the sulphuric acid should be concentrated or dilute.
iii) the reaction of hydrogen chloride with Ammonia.
iv) the reaction when excess Ammonium hydroxide is added to copper sulphate solution.       (4)

Question 6
a) i) Write the general formula of the aldehyde homologous series. Also write the name of first member of this series.
ii)  How is acetic acid formed from ethanol ? Write equation only.    (3)

b) (Ethane, Ethene, Ethyne, Ethanol, Ethanal, Ethanoic acid)
From the box given above , Name .
i) the compound with -- OH as the part of its structure.
ii) the compared with --- COOH as the part of its structure.
iii) the compound with --- CHO as the part of its structure.    (3)

c) Write the equations for the following laboratory preparations:
i)  ethane from sodium propionate
ii) ethene from iodoethane.
iii) Ethyne from calcium carbide
iv) methanol from iodomethane.      (4)


Question 7
a) Arrange the metal iron, zinc, copper, sodium and magnesium in decreasing order of reactivity.    (1)

b) When dilute hydrochloric acid is added to a solution of Lead Nitrate in a test tube, a white participate is formed .
i) Name the white participate formed.
ii) Write the balanced equation.
iii) What is seen as the test tube cools down
iv) What happens when the precipitate is heated with water    (4)


c) Distinguish between a mineral and an Ore.
ii) Name the process involved in the concentration of ores.
iii) State two object achieved during roasting of an ore.
iv) Name the constituent of invar.
v) Name an alloy of zinc which is used to simple voltaic cells.      (5)


















TEST PAPER - 1 

Section I 
(Compulsory: To be attempted all)

Question 1.           (3)
a) Name the following:
i) The gland which secrets insulin.
ii) The part of the brain which is concerned with memory.
iii) The kind of cells which constituted the cortex in a root.


b) Given below is an example of a certain structure and the special functional activity with which it is concerned:    (4)
e.g., white blood cell and the phagocytosis 
On a similar pattern, fill in the blanks in the following pairs to represent relationship between the structures and their special functional activity.
i) _____and ultrafiltration(in kidney)
ii) Myelin Sheath and ____
iii) Spinal cord and ____
iv) seminiferous tubeles and ____


c) Select one suitable word from the three alternatives given to fill the blanks in the following sentences:      (5)
i) The foetus draws its oxygen from the__''(amniotic fluid/placenta/ umbilical cord)
ii) The condition of a cell when it cannot accommodate any more water is____ (turgor pressure/ turgid/ flaccid)
iii) The blood vessel which carries oxygenated blood to the heart is___(aorta/ pulmonary vein/ pulmonary artery)
iv) The respiratory Centre is located in the____( cerebrum/ hypothalamus/ Medulla oblongota)
v) Myopia can be corrected by____(convex lens/ concave lens/ surgery)


d) Study the diagram given alongside and answer the questions that follow:    (5)
i) Will the level in the thistle funnel rise or fall ?
ii) Give the reason to explain your answer.
iii) Name one place where this process occurs in the human body and one place in plants.
iv) What would happen if the above membrane was freely permeable ?


e) State one difference in each of the following pairs on the basis of what is indicated in brackets after each.     (2)
i) Cerebrum and Cerebellum (function)
ii)  Corpus callosum and Corpus luteum( location)


f) Mention whether the following statements at true or false:    (4)
i) Presbyopia is generally an age related eye defect.
ii) Root hair are the extension of the outer epidermal cell of the root.
iii) Oversecretion of thyroxin causer simple goitre.
iv) A dicot leaf is isobilateral.


g) State one man function of the following: (2)
i)  iris
ii) pituitary gland.


h) Write the odd one out and give reason for your answer. (2)
i) glycolysis, photosynthesis, photolysis, carbon dioxide fixation.
ii) Spleen, thymus, pancreas, tonsil.


Section II 
(Answer any four questions from this section)

Question 2

a) The following represents an experimental performed to demonstrate a particular aspect of photosynthesis. Study the diagram and answer the question that follow: (5)
i) What is the object of this experiment.
ii) What is the chemical marked 'X'?
iii) What will you observe when you test leaf Y with iodine solution ?
iv) Name the process which is the reverse of photosynthesis in terms of the end products.
v) Write the overall equation for the process named in (iv).


b) Define the following: (2)
i) plasmolysis 
ii) Gestation 


Question 3
a) The figure below represents the vertical section of a leaf.    (5)
i) Name the parts level 1 to 5.
ii) What do you two arrows (dotted and solid) indicate in the day time and at night ?
iii) How many leaf veins have been shown in this section ?


Question 4.      
a) Differentiate between the following:     (5)
i) Blood plasma and serum
ii) Neuron and nephron
iii) Transpiration and Guttation 
1v) night blindness and colour blindness

b) Given below is a diagram of the external features of the heart:   (5)
i) Name the part 1 to 7.
ii) What happens if the coronary atery gets an internal clot ?
iii) Mention one structural difference between 5 and 4.



Question 5.         (5)

a) i) Draw a diagram of the human excretory system and label the following:
Renal cortex, renal Medulla , renal pelvis, ureter, urinary bladder and Urethra 
ii) List the main constituents of the normal human urine .
iii) Name the blood vessels which enter the leave the kidney.

Question 6
a) Given below are different stages in the fertilization of an egg.   (5)
i) Arrange the stages in the correct order as they would have taken place.
ii) In the female reproductive system where does this process takes place?
iii) Differentiate between identical and fraternal twins .
iv) What is meant by the colostrum ? State its function.


Question 7
Explain briefly the following statements :
a) Abnormally large numbers of WBC in the blood is usually an indication of some infection in our body.     (2)
b) Veins have valves at intervals in their inner lining whereas arteries do not have valves.      (2) .
c) Most often only one embryo is found at a time, although there are two ovaries in women.
d) Insulin is injected into the body of a highly diabetic patient and not given orally.