PERIODIC TABLE

       PERIODIC PROPERTIES

A) FILL IN THE BLANKS :
1) The serial number of an element in the Periodic Table is also its.....
2) The metallic character.... in a Group as one moves from top to bottom.
3) The metallic character... in a Period as one moves from left to right.
4) ....is the most active nonmetal.
5) ....is the most active metal.
6) An increase in nuclear charge... the tendency of an atom to accept electrons.
7) The atomic size....as one moves from left to right across a Period.
8) The element in Group VIIA which is a liquid at room temperature is....
9) Nuclear charge of an atom is the... charge on the nucleus of an atom, equivalent to the atomic...of an atom.
10) Atomic size of neon is...than the atomic size of fluorine.
11) With increase in nuclear charge the nuclear attraction for outer electron..... . Hence ionisation potential......
12) If an element has one electron in its outermost shell. Then it is likely to be.....
13) The Properties of elements are periodic function of their....
14) The element below sodium in the same Group would be expected to have a..... . electronegativity than sodium and the element above chlorine would be expected to have a..... . ionisation potential than chlorine.
15) On moving from left to right in a given Period, the number of shells..
16) On moving down a Group, the number of valence electrons.......

Choose the correct answer from the choices a, b, c, d.

1) The chemical properties of an element depends on its:
a) atomic mass
b) atomic number
c) atomic energy
d) atomic volume
2) Total number of vertical columns (Groups) in the Long Form of the Periodic Table is :
a) 8 b) 18 c) 17 d) 16
3) The element having the lowest ionisation potential in period 3 is:
a) Na b) K c) Mg d) Al
4) The number of elements present in Period 3 is :
a) 6 b) 32 c) 18 d) 8
5) On going down a Group, the number of valence electrons.
a) increases  b) decreases
c) remains the same
d) varies irregularly
6) The number of Periods in the Long Form of Periodic Table is:
a) 6 b) 7 c) 8 d) 10
7) On moving down a Group, the size of atoms :
a) increases  b) decreases
c) remains the same
d) varies irregularly
8) Which one of the following ions has the smallest radius ?
a) Cl⁻      b) K⁺    c) S²⁻    d) Ca²⁺
9) On moving from left to right in a Period the metallic character of elements:
a) increases
b) decreases
c) remains the same
d) varies irregularly
10) The correct order of decreasing first ionisation potential is :
a) C > B > Be > Li
b) C > Be > B > Li
c) B > C > Be > Li
d) Be > Li > B > C
11) Which halogen has the highest electron affinity ?
a) F b) Cl c) Be d) I
12) The most electronegative element in the Period Table is:
a) N b) O c) Cl d) F
13) Which has the smallest size?
a) Na⁺  b) Al³⁺   c) Mg²⁺ d) P⁵⁺
14) Which of the following is the correct order of ionisation potential in the Periodic Table?
a) F > O > N > C
b) O > F > N > C
c) O > N > F > C
d) C > N > O > F
15) The electron affinity for noble gases is likely to be:
a) high b) small c) zero d) Positive
16) Which of the following has the highest electron affinity?
a) F b) O c) O⁻ d) Na⁺
17) The size of a positive ion is:
a) more than its atom.
b) less than its atom
c) equal to its atom
d) none of the above
18) Which one of the following is correct order of the size ?
a) I > I⁻> I⁺
b) I >  I⁺> I⁻  
c) I⁺ > I⁻> I  
d) I⁻ > I > I⁺
19)The size of chloride ion (Cl⁻) is
a) smaller than chlorine atom
b) bigger than chlorine atom
c) equal to that of chlorine atom
d) none of the above
20) The ionic radii of  N³⁻ , O²⁻ ,  F⁻ and  Na⁺ follow the order
a)  N³⁻ >  O²⁻ > F⁻ > Na⁺
b)  N³⁻ >  Na⁺ > O²⁻ >  F⁻ 
c)  Na⁺> O²⁻  > N³⁻ > F⁻ 
d) O²⁻ > F⁻  > Na⁺ > N³⁻

B) NAME THE FOLLOWING:
1) The element present in the first Period.
2) The biggest atom in the third Period.
3) The smallest element of third Period
4) The family of elements to which chlorine belongs.
5) The family of elements to which sodium belongs.
6) The family of elements to which argon and neon belongs

7) A solid halogen.  
8) Least electronegative element of halogen family.
9) A non metal which has three electrons in its outermost shell
10) The smallest atom in the third Period
11) The least reactive elements in Group IA.
12) The most metallic element in the third Period.
13) The most nonmetallic element in the third Period
14) The element which is most electronegative in the third Period
15) A greenish yellow gas other than chlorine..
16) The most abundant halide salt.
17) The element which has the highest ionisation potential.
18) The element of third Period which has least ionisation potential
19) The most electronegative element of second period
20) An element in period 3 with electronegativity 3.0
21) The element with the least ionisation potential in the 2nd period.
22) The element which has the highest electron affinity in the third Period
23) The noble gas having an electronic configuration 2,8,8.
24) The valency of elements in Group I.
25) An element of group VIIA, solid at room temperature.

C) TRUE/FALSE
1) The electron present in the outermost shell are called valence electrons.
2) In a group, atomic and ionic radii decrease from top to bottom due to increase in the number of shells.
3) The electron affinity of elements increases in a group from top to bottom and decreases along a period from left to right.
4) The amount of energy required to remove a loosely bound electron from the outermost shell of an isolated atom is called ionisation potential.
5) Electron affinity is the property of an atom to attract electrons towards itself, when combined to form a compound.
6) Lithium resembles radium and potassium in electropositive character and univalency.
7) The element in a Group have consecutive atomic Numbers.
8) On going down in a group of the Modern Periodic table, the metallic character of elements increases.
9) The tendency of an atom of an element to donate or lose electrons is called electropositivity.
10) Iron is a non-metal.

D) DEFINE:
1) Periods in Periodic table
2) Group in Periodic table
3) Periodicity

E) ANSWER THE FOLLOWING:
1) How many electrones are present in the valency shell of the element with the atomic number 18
2) From amongst Be,  B, and C, choose the element with the highest ionisation potential
3) What is similar in the electronic structure of Li, Na, and K
4) Which of the following elements are in the same Group of the Periodic table. Magnesium, nitrogen, beryllium, sulphur
5) Which group of elements was missing from Mendeleev's original Periodic table
6) State the Periodic law on which Mendeleev's Periodic table was based
7) What similarity do halogen show in their molecular state
8) If an element is in Group 7(or group 7A) is likely to be metallic or nonmetallic in character
9) Predict the group of an element X if it's atomic number is 16.
10) Select the correct order f radii of three species Ca, Ca⁺ and Ca²⁺
11) The elements lithium, sodium and potassium were put in one group on the basis of their similar properties.
a) What are those similar properties
b) What is the usual name of this Group or family.
13) What is the cause of periodicity of elements in the Periodic table.
14) In which part of a Group would you separately expect the elements to have:
a) the greatest metallic character
b) the largest atomic size
14) a) What are alkali metals?
b) In which Group and subgroup are they placed ?
c) What is their valency
d) Why do they not occur free in nature?
15) a) What are noble gases?
b) what is the speciality of their outermost shells
c) Why is that group referred to as Zero Group
d) Why are they referred to as inert gases ?

F) REASON BEHIND:
1) Why electron affinity of atoms increases from left to right along a period in the Modern Periodic table
2) Why the elements with low ionisation potential exhibit metallic character.
3) Sodium is referred to as a normal element.
4) Sodium and potassium are placed in group I
5) Electron affinities of two elements A and B are as follows
A=3.79 eV and B= 3.56 eV which of them will ionise more easily and why ?
6) Which is larger, Na⁺ or K⁺ ? Why?
7) Why is the electron affinity for F Less than that of Cl?
8) Why electron affinity of halogen is comparatively high
9) Ionisation potential of alkali metals is comparatively low.
10) Why is chlorine more reactive than bromin ?
11) Why Potassium is more reactive than sodium.
12) Why is ionisation potential of O is less than that of N

TEST PAPER-1(Biology) (X)

Attempt all questions from Section I and any four questions from Section II

The intended marks for questions or parts of questions are given in [ ].

*********************************

Question 1.

a) Name the following:

I) cytoplasmic organelles that helps in manufacture of starch.

ii)

iii) pair of genes responsible for a particular characteristics in an individual.

iv) A solution whose concentration is greater than that of the cell sap.

v) the fluid that provides protection and nourishment to the cells of the brain.              (5)

b) State whether the following statements are true or false, write the correct statement by changing the incorrect word words only the number of word/s only.             (5]

I)

ii) 

iii) rods are responsible for reason in the dark.

iv) The dark reaction of photosynthesis light independent.

v)                                        [5]

c) Match the items in column A with those which are most appropriate in column B. you must rewrite the matching pairs.

Column A

1. basic units of life

2. Beta cells of pancreas

3. Meiosis

4. protective covering of the brain

5. construction of the pupil of the eye

Column B

A.  glucagon 

B. Meninges

C. Iris

D. cell 

E. insulin

F. Skin cell

G. Protoplasm

H. Sperm

I. Ciliary muscles.                    (5)

d) DIAGRAM OF POTOMETER

I) name the apparatus

ii) mention one limitation of this apparatus

iii) what is the function of the part marked ' reservoir'?

iv) what is the role of the air bubble in the experiment?        (5)

e) In the box given below is a list of biological terms that can be used to complete statements that follows. select the appropriate term from the box and rewrite the completed statement. you may use a term only once.

( concave, neuron, lactic acid, glucose, animal waste, Gestation, nerve, ethyl alcohol, nephron, myopia, DDT, pregnancy, convex)

I) the type of lens used to correct myopia is ____

ii) the basic unit of human brain is the ____

iii) The end product of  fermentation is _____

iv)

v)                                   (5)

f) given below are the function of cell organ/structures found in living organisms. in each case, name the organs or structure that;;

I) produces testosterone

ii) is responsible for protecting the eye from sweat.

iii) transmits characteristics from parent to offspring.

iv) transport water from the soil to other parts of the plant.

v) initiates cell division.          (5)

G) Explain the following term:

I) Tropic hormone 

ii) guttation

iii) osmosis

iv) stereoscopic vision 

v) Mutation.        (5)

h) given below is a set of terms arranged in logical sequence, representing a process or a function. of these, one terms is incorrect. identify the incorrect term and replace it with the correct term. one has been done for you as an example.

 Pollen Grain --> exine--> staminal Tube--> male gametes--> micropyle

incorrector term--  staminal tube. correct term-- pollen tube.

I)

ii) soil water--> root hair--> cells of cortex --> epidermis--> xylem

iii) 

iv) pupil--> eye lens--> vitreous humour--> fovea--> auditory nerve.

iv) Sensory nerve--> dorsal root ganglion -->sensory neurone--> motor neurone -->receptor.     (5)

             SECTION II (40 MARKS)

             *.  *************** .*

Attempt any four questions from this section

Question 2.

a) differentiate between the following on the basis of what is given in the brackets.

I)

ii)Karyokinesis and Cytokinesis ( explain the terms)

iii) 

iv) mitosis and Meiosis (number of daughter cells formed)

v) pure and hybrid strains(definition).            (5)

b) Diagramatic question.     (5)

Question 3

a) Answer the following questions briefly:

I)

ii)

iii)

iv).                      (5)

b) Diagramatic question.     (5)

Question 4.

a)I) Draw a neat and well labelled diagram of the chloroplast.

ii) list the events taking place in the photochemical phase of photosynthesis.

iii) If you are planning an experiment to show the effect of light on photosynthesis :

   1) will you select white light or green light ? justify your answer

  2)  why would you select a destarched plant.                    (5)

b)I)explain the term reflex action. 

ii) Expand the following biological Abbreviations

     1) DNA    2) AIDS

iii) State whether the following actions are voluntary action, simple reflex or conditioned reflex:

  1) blinking 

  2) cleaning the table

  3) playing on the keyboard

  4) salivating when food is put into the mouth.                   (5)

Question 5:

a) Diagramatic question on eye

I)

ii)

iii)

iv).                      (5)

 

b) Name the hormone which lead to the following conditions:

I) Diabetes mellitus

ii) growth of beard in women

iii) myxoedema

iv) Gignatism

v) exophthalmic Goitre.       (5)

Question 6)

a) Diagramatic question.      (5)

b)I) State mendel's Law of independent assortment.

ii) A homozygous Tall plant (T) bearing red coloured (R) flowers is crossed with a homozygous Dwarf plant(t) bearing white flowers (r)

 1. give the genotype and phenotype of the F' generation.

 2.  give the possible combinations of the gametes that can be obtained the F' hybrid.

 3. Give the dihybrid ratio and the phenotype of the offspring of the F" generation when two plants of the F' generation above are crossed.          (5)

 Question 7)

a) The Diagramatic question of mitotic cell division.         (5)

b) Give reason for the following:

I) plants begins to die when excess of soluble fertilizers are added to the soil.

ii) Injury to the medulla oblongata results in death.

iii) Gametes have a haploid number of chromosomes.

iv) Green leaves are thin and broad.

v) Lysosomes are termed  suicidal bags of a cell.              (5)

WATER

A) Water occurs both in free and in the combined state in solid, liquid or gaseous(vapour) state. NAME the following forms of water.
1) water occurring in the combined form in a mineral salt.
2) A naturally occurring gaseous state of water other than water vapour.
3) A liquid free state of occurrence of water above the Earth's surface.
4) A food product containing a large percentage of water in the combined form.
5) An occurrence of water in the free state in the solid from other than ice.
6) Water occuring in the liquid form in the free state below the Earth's surface.

B) With reference to the following three properties of compounds, give reasons why water is considered as a compound not an element.
1) Always homogeneous with particles of one kind.
2) Have a definite set of properties and components do not retain their original properties.
3) the components can be separated by chemical means only.

C) water found in the natural state is called 'natural water' while that which has received some form of treatment is called "treated water". NAME:
1) Two sources of natural water other than rain water, river and lake water.
2) the purest form of treated water free from all minerals solutes prepared by condensing steam.
3) a form of treated water  prepared by filtration followed by chemical treatment and is generally used for drinking purposes,
4) An acidic gas used for killing germs present in the water in swimming pools.

D) Choose is the correct word/ statement related to the physical properties of water.
PHYSICAL PROPERTIES:
1) boiling point of water increases and freezing point decrease.
2) water at 4° C has
3) water has the highest specific heat capacity requires
4) water exhibits anamalous expansion hence on cooling
5) in terms of conductivity, water is a
OPTIONS
a) with increase in pressure on the surface of the water.
b) with decrease in pressure on the surface of the water.

a) minimum density and maximum volume.
b) maximum density and minimum volume.

a) less heat to raise its temperature by 1° C.
b) More heat to raise its temperature by 1°C.
- then an equal mass of any other substance.

a) first expands but at  temperature at 4° C starts contracting.
b) first contracts but at temperature at 4° C expanding.

a) bad conductor of heat but a good conductor of electricity.
b) bad conductor of heat and electricity.

E) GIVE reason for the following:
1) water existed all the three States of matter.
2) water finds application in modifying the climatic conditions of the land adjacent to large areas of water.
3) water has the ability to dissolve electrovalent compound e.g., sodium chloride.
4) Carbon disulphide is considered a solvent while water is a universal solvent.
5) marine life exists below lakes.
6) Benzene does not exhibit anomalous expansion but water does.

F) MATCH the statement in column I with their continuity in column II
COLUMN I
1) dissolved oxygen in water used for
2) photosynthesis in aquatic plants takes place by utilising the
3) insoluble limestone layers in water are
4) Marine animals make or strengthen their shells by
5) in photosynthesis dissolved carbon dioxide is utilised for the formation of Carbohydrates and the evolved gas is

G)
COLUMN II
a) carbon dioxide present in dissolved water.
b) oxygen
c) dissolved in the presence of carbon dioxide in water resulting in formation of soluble bicarbonates.
d) Respiration by aquatic animals.
e) absorbing the calcium carbonate from the soluble calcium bicarbonate in water.

H) Complete and balance the equation pertaining to the importance of carbon dioxide dissolved in water.(X= carbon dioxide )...
PHOTOSYNTHESIS
______+ H₂O --> _____+ H₂O+ ____
   (X)               glucose

FORMATION of SHELLS BY MARINE ANIMALS
________+ H₂O+_____->________
insoluble layer   (X)      absorbed
                                     soluble layer

I) NAME THE METAL WHICH
1) reacts with cold water and sinks in it.
2) turns with a coloured flame on a reaction with cold water.
3) forms a residual milky, turbid solution with cold water.
4) is generally amalgamated and added to cold water for collection of liberated hydrogen.
5) does not react with cold water, but reacts slowly with boiling water.
6) does not react with cold or boiling water but reacts with steam and trivalent.
7) reacts comparatively very slowly steam and undergoes a reversible reaction.
8) reacts with steam forming an amphoteric oxide, yellow when hot white when cold.

J) GIVE REASON::
1) syntheses of hydrogen chloride from its elements takes place in the presence of moisture.
2) sodium is amalgamated(ie., alloyed with mercury) when used for collection of the liberated hydrogen, on reaction with cold water.
3) Magnesium and aluminium react with steam but the reaction soon comes to a stop. Further heating to high temperatures renders the metal active again, liberating hydrogen.
4) sodium reacts with cold water, magnesium with boiling water while iron with steam only.

K) Complete and balance the following equation for reactions of different metals (X) with water.

1) ___+ H₂O --> __+ H₂ [X burns
             cold
with a lilac flame in air]

2) ____+ H₂O --> ___+H₂ (X is
              cold
divalent and sinks in water)
3)____+ H₂O -->_____+ H₂ (X is
              steam              trivalent)

4)_____+ H₂O--> ___+H₂ (is an
              steam  amphoteric oxide,
                           yellow when hot)

5)___+ H₂O <=>___+H₂  (Z is a
         steam                mixed oxide)

L) Name the acid/acids formed when the following gases are dissolved in water in a give a balanced equation for the same.
                    product- acid/s    equ..
1) chlorine
2) Sulphur Dioxide
3) sulphur trioxide
4) carbon dioxide
5) Nitrogen dioxide

M) A liquid 'X' is to be treated for water.
1) give two physical tests to prove that liquid is water.
2) using
  (i) copper sulphate,
(ii) Cobalt chloride; state the colour change observed when the above anhydrous salts turn hydrous.

N) STATE THE FUNCTION OF WATER in the following:
1) As a solvent
2) Un nature
3) In industry
4) In the human body

O) SELECT the correct statement in the table given below for the properties of a true solution.
TRUE SOLUTION
1) A true solution is
2) the particles in a true solution
3) the solute present in the solvent of a true solution can be recovered by.
4) a true solution is a
OPTIONS:
a) clear and homogeneous in nature
b) translucent and heterogeneous nature

a) are molecular, and con be seen under a microscope
b) are molecular, cannot be seen under a microscope
c) pass through the pores of filter paper, and slowly settle down.

a) chemical and not by physical means
b) physical and not by chemical means

a) compound  b) mixture

P) DIFFERENTIATE BETWEEN:
1) saturated solution/ Unsaturated solution
2) saturated solution/ supersaturated solution
3) dilute solution/concentrated solution
4) dissolution of sodium chloride in water/low melting of ice in water

Q) GIVE REASON:
1) A saturated solution can be converted to an unsaturated solution by heating the saturated solution very slowly.
2) Conversation of saturated solution to an unsaturated one can also be brought about by adding more of the solvent to the saturated solution.
3) cooling hot saturated solution prepared at high-temperature results in formation of supersaturated solution.
4) A satuated solution can be distinguished from an unsaturated solution using a small crystal of the solute used in the preparation of the above solutions.

R) Match the appropriate solvents in column I with the solute ii dissolves in column II
COLUMN I
1) carbon disulphide
2) oxalic acid
3) Acetone
4) liquor Ammonia
5) petrol
6) turpentine oil
7) iodine
8) Benzene
COLUMN II
a) grease stains (by emulsifying)
b) chlorophyll
c) paint
d) alcohol
e) sulphur
f) cellulose acetate(nail polish)
g) rust
h) rubber

S) Complete the definition of the ' solubility of a solute in a solvent' by selecting the correct word in each case.
=> THE SOLUBILITY of a solute in a solvent at a particular temperature/pressure is the minimum/maximum amount of the solvent/solute in grams/litres that will saturate/dissolve in, 100 grams of the solvent/solution at that temperature.

T) An experimental procedures is involved in determining the solubility of a solute at t°C. The points A, B, C, D, E, F, G are the steps involved in determining the 'solubility of KCl'' but the order is in correct. Place the points in the correct order.
1) weigh a clean dry evaporating dish and add the prepared saturated solution of KCl to it.
2) Add KCl crystals to distilled water, stir slowly till the crystal dissolve.
3) Heat the saturated solution in the evaporating dish to dryness and reweigh the dish with the residue.
4) Reweigh the evaporating dish with the saturated solution in it.
5) make a saturated solution of KCl by adding more of the solute till no more of the solute dissolves.
6) calculate the solubility of the solute at the noted temperature using the formula:
Solubility=Wt. of solute/Wt. of solvent × 100

U)  during the determination of the solubility of a solute the following calculations were noted.
a) Dry evaporating dish= Mg.
b) evaporating dish+ saturated solution= M₁g.
c) Dish+ Residue after heating above saturated solution to dryness= M₂g.
In terms of M, M₁ and M₂ complete the result of the solubility of the solute.
solubility= _____/____× 100 at t°C

V) With reference to "solubility of Potassium Chloride in water" answer the following:
1) the solubility of KCl in water is 60g at 97°C. Explain the statement.
2) State one way by which solubility of KCl in water can be increased.

W) GIVE REASON:
1)a) temperature is always specified when stating the solubility of a solute(eg , KCl) in a solvent (eg., Water).
b) when 830ml of a saturated solution of salt 'X' is cooled from 75° C to 35°C a large amount of crystals are deposited out from the saturated solution on cooling,  but when 800 ml of saturated solution of salt 'Y' is cooled from 75°C to 35°C the amount of crystal deposited out are much less.
2) 20 gram of saturated solution of salt X at 60° C contains 50g of the salt. calculate the solubility of the salt X at 60° C.
3) A saturated solution of salt Z at 50°C is evaporated to dryness.  salt solution was used is 20.5 CM calculate the solubility of the salt at 50° give reason for the following chalo bolati kab point utility truck pahchan biopharma copper used for extraction of chemicals from their sources purification verification and separation of solutes can be carried out comparatively easily with the knowledge of solubility craft solubility curve complete the statement using the correct about an increase in pressure on the surface of water causes and increase decrease insulin bility of a gas in the water while in an increase in temperature of water causes a decrease in increasing the solubility of gas in water give reason for the following in the manufacture of Open Water before and after that in the box differentiate between the following give reason for the following hot saturated solution slowly followed by flow operation of the solution without any crystal from the solution of sodium chloride to not contain water of crystallization you are provided with a saturated solution of 90° c h a glass rod played Muslim cloth using the above give the namespace for the obtaining a well-defined Bristol United state two conditions for obtaining a large chemical names of the Crystal in column 1 with their common names in colony to sodium carbonate calcium sulphate ferrous sulphate copper sulphate magnesium sulphate sodium sulphate calcium nitrate sodium nitrate Ammonium Nitrate green vitriol epsom salt for child for blue vitriol landform Pita washing soda cell Ammonia night monohydrate dihydrate trihydrate pentahydrate hydrate decahydrate anhydrous efflorescent deliquescent hygroscopic substances and drying agent complete the following terms using the correct words substance with anhydrous hydrated salt with atmosphere loses completely and changes into liquid state the water soluble Airtel question substances soluble salt which on exposure to the atmosphere absorb loses is called in the observed changes into a liquid state loses from atmosphere when exposed does not undergo any change in state name the following substance other than washing soda and caustic alkali solid hygroscopic substances used for trying ammonia as a desiccating agent agent crystal which is the chloride of a drying agent used for trying sulphur sulphur dioxide a basic oxide other than quicklime which is hygroscopic nature I install deliquescent in nature for the following options is the minimum during humid conditions while the lips during dry condition potassium chloride is not deliquescent and hence doesn't not exposed to the atmosphere common salt is not exposed to the atmosphere acceptances from Delhi distance

MOLECULE

1) How many molecules are in:

a) 0.71g of chlorine gas. Take Avagadro's number as 6x10²².   6x 10²¹

b) 3.65g of HCl gas. (A. N= 6x10²³).    6x 10²²

c) 

2) calculate the weight of:

a) 10.0 atoms of sodium (1 a m.u= 1.6603x1/10²⁴g).            3.82/10²²

b) 2x10²³ molecules of copper sulphate. (A. N= 6x10²³).       5.33

c) 4x 10²⁴ molecules of SO₂.   0.3012 x 10²³.

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

VALENCY CHART

               VALENCY CHART

_________________________________

ELECTROVALENT POSITIVE IONS/ RADICALS

--------------------------------

VALENCY1- Monovalent elements

                *******************

* Potassium         K¹⁺

* Sodium              Na¹⁺

* Lithium              Li¹⁺

* Hydrogen          H¹⁺

* Ammonium     NH₄¹⁺

          • Variable valencies

* Cuprous.  [Copper (I) ]           Cu¹⁺

* Argentous [Silver (I) ]             Ag¹⁺

* Mercurous [Mercury (I)]        Hg¹⁺

* Aurous [ Gold(I)]                     Au¹⁺

VALENCY 2 - Divalent elements

           ********************

* Calcium                      Ca²⁺

* Magnesium               Mg²⁺

* Zinc                             Zn²⁺

* Barium                        Ba²⁺

* Nickel                          Ni²⁺

* Cobalt                         Co²⁺

* Uranium                       U²⁺

       • Variable valencies

*Cupric [ Copper (II)]               Cu²⁺

* Argentinc [Silver(II)]             Ag²⁺

* Mercuric [Mercury (II)]        Hg²⁺

* Ferrous [Iron(II)]                   Fe²⁺

* Plumbous [Lead(II)]            Pb²⁺

* Stannous [Tin(II)]                 Sn²⁺

* Platinous [Platinum (II)]      Pt²⁺

* Mangannous

         [Manganese (II)]           Mn²⁺

VALENCY 3 - Trivalent elements

              ****************

* Aluminum                             Al³⁺

* Chromium                            Cr³⁺

         • Variable valencies

* Ferric [Iron (III)]                   Fe³⁺

* Auric [Gold (III)]                  Au³⁺

VALENCY 4- Tetravalent elements

              *********************

        • Variable valencies

* Plumbic [Lead(IV)]                Pb⁴⁺

* Stannic [Tin(IV)]                    Sn⁴⁺

* Platonic [Platinum (IV)]        Pt⁴⁺

* Mangannic 

      [Manganese (IV)]              Mn⁴⁺

        

ELECTRO NEGATIVE ION/RADICALS

-----------------------------------------------------

VALENCY1- Monovalent elements

            ******************

* Chloride                                Cl¹⁻

* Chlorate                              ClO₃¹⁻

* Hypochlorite                      ClO¹⁻

* Bromide                                Br¹⁻

* Iodide                                     I¹⁻

* Hydroxide                            OH¹⁻

* Nitrite                                   NO₂¹⁻

* Nitrate                                  NO₃¹⁻

* Hydrogen [bi] carbonate  HCO₃¹⁻

* Hydrogen [bi] Sulphite     HSO₃¹⁻

* Hydrogen [bi] sulphate    HSO₄¹⁻

* Aluminate                           AlO₂¹⁻

* Permanganate                   MnO₄¹⁻

VALENCY 2- Divalent elements

         *******************

* Sulphite                             SO₃²⁻

* Sulphate                            SO₄²⁻

* Sulphide                              S²⁻

* Carbonate                         CO₃²⁻

* Oxide                                   O²⁻

* Chromate                         CrO₄²⁻

* Dichromate                      Cr₂O₇²⁻

* Peroxide                              O₂²⁻

* Silicate                               SiO₃²⁻

* Zincate                              ZnO₂²⁻

* Plumbite                            PbO₂²⁻

VALENCY 3- Trivalent elements

        ******************

* Phosphate                         PO₄³⁻

* Nitride                                  N³⁻

* Phosphate                          PO₃³⁻

VALENCY 4- Tetravalent elements

* Carbide                                C⁴⁻

Compound formed from elements with variable valency

Element.          Valency   Compund

* Copper.  • Cuprous 1 

                 Copper(I) oxide Cu₂O

                    Cupric    2

                 Copper(II) oxide CuO

* Iron.       • Ferrous   2 

                 Iron(II) oxide   FeO

                 • Ferric      3

                Iron(III) oxide   Fe₂O₃

* Mercury • Mercurous  1 

                Mercury(I) oxide Hg₂O

                  •  Mercuric  2

               Mercury(II) oxide HgO

WRITING THE FORMULA OF CHEMICAL COMPOUNDS

_________________________________

STEP I: Write the symbol- of the positive atom or radical on the left side and the symbol of the negative atom or radical on the right side. As

1) Na         Cl           2)   CA      SO₃ 

3) Cr         SO₄          4)  Ca     HSO₃

STEP II: Write the valency number on the symbol- of each atom/radical on its top right side.

1) Na¹⁺      Cl¹⁻       2) CA²⁺     SO²⁻   

3) Cr³⁺       SO₄²⁻    4) Ca²⁺   HSO₃¹⁻

STEP III: Interchange the valency number- of each atom or radical and shift it to the lower right side of the atom or radical. In case the valency number of both the atoms or radicals is the same i.e., above 'one' divide by the higher common factor to get a simple ratio. Ignore the (+) and (-) sign on each symbol. If the valency number of radical in the compound is above two of then enclose the radical in a bracket with the number on the right of the bracket at the bottom.

      ₁          ₁                  ₂            ₂

1) Na      Cl           2) CA        SO₃  

      ¹          ¹                  ²            ²

      ₃          ₂                   ₂          ₁

3) Cr       SO₄          4) Ca      HSO₃

      ²          ³                    ¹           ²

STEP IV: Write down the formula of the compound- on interchanging if valency number is 'one' the figure 'one' is never written.

1) NaCl                   2) CaSO₃

3) Cr₂(SO₄)₃           4) Ca(HSO₃)₂

RULES IN NAMING CERTAIN CHEMICAL COMPOUNDS

_________________________________

Compound containing

-----------------------------------

1. A metal and a nonmetal.

RULE

• Metal is written first

• Nonmetal given a suffix - ide

EXAMPLE:

Compound containing potassium and iodine.

Potassium       +             Iodine

⁽ᵐᵉᵗᵃˡ⁾                            ⁽ⁿᵒⁿᵐᵉᵗᵃˡ⁾

Formula : Potassium iodide.

Compound containing

------------------------------------

2) Two nonmetals only.

RULE

• Nonmetals written side by side.

• Nonmetal given a prefix - mono, di, tri, etc. denoting the no. of atoms.

EXAMPLE:

Oxides of nitrogen

Dinitrogen oxide-          N₂O       +1

Nitrogen monoxide-     NO        +2

Dinitrogen trioxide-      N₂O₃      +3

Nitrogen dioxide-          NO₂       +4

Dinitrogenpentoxide-   N₂O₅      +5

⁽⁺¹ᵗᵒ ⁺⁵ ᵈᵉⁿᵒᵗᵉˢ ᵒˣⁱᵈᵃᵗⁱᵒⁿ ⁿᵒ· ᵒᶠ ⁿⁱᵗʳᵒᵍᵉⁿ⁾

Compound containing

-----------------------------------

3. Two elements and oxygen.

RULE

• Two elements written side by side. Oxygen written after it.

• Oxygen is named with suffix

        ⁻ ᵃᵗᵉ ⁽ᵒⁿᵉ ʷⁱᵗʰ ᵐᵒʳᵉ ᵒˣʸᵍᵉⁿ⁾

        ⁻ ⁱᵗᵉ ⁽ᵗʰᵉ ᵒⁿᵉ ʷⁱᵗʰ ˡᵉˢˢ ᵒˣʸᵍᵉⁿ⁾

EXAMPLE:

Potassium chlorate - KClO₃

Potassium Chloride - KClO₂

[Elements also given prefix -hypo or -per depending on oxygen content]

Potassium hypo-chlorite -    KClO

Potassium per-chlorate -      KClO₄

MOLE (NUMERICALS)

A) How many grams are there in:

a) 2 moles of oxygen.              64g

b) 0.01 mole of nitrogen.      0.28g

c) 0.5 mole of O₂.                      16g

d) 0.2 mole of H₂.                      0.4

e) 0.2 mole of Al.                       5.4

f) 0.1 mole of HCl.                  3.65g

g) 0.2 mole of H₂O.                     3.6

h) 0.1 mole of CO₂.                   4.4g

B) How many mole atoms are there in:

a) 112g of Iron.                             2

b) 48g of oxygen.                          3

c) CO₂ which contains 8g of O₂.   0.25

d) 0.8g of methane.                  0.05

C) Which of the following would weigh most ?

a) 1 mole of H₂O

b) 1 mole of CO₂

c) 1 mole of NH₃     

d) 1 mole of CO

LANGUAGE OF CHEMISTRY.(1)

*** A symbol represent a short form of an element.

A)

a) In most cases the first letter of an element was taken as a symbol for that element. Give two examples of the same.

b) In certain cases the first letter along with its small letter from its name were used as the symbols. Give two examples of the same.

c) I some cases the symbols were derived from their Latin names. Name two metals whose symbols are derived from the same.

d) Sulphur is represented by 'S'. State how the symbol represents the elements 

a) qualitatively(i.e , representation in terms of an atom) 

b) quantitatively,(representation in terms of weight).

2) Explain the meaning of the terms in Italic given below.

    For writing a chemical formula the symbols and the valency of the element or radical should be known :

3) GIVE REASON: 

a) In hydrogen chloride the valency of the element chlorine is considered as one.

b) Certain metals exhibit more than one valency hence showing 'variable valency'.

4) Electro positive ions radicals

Symbol/valency               name

a. K ¹⁺                            potassium

b. Na

c. H

d. NH₄

e. Ca

f. Mg

g. Zn

h. Ba

i. Ni 

j. Co

k. Al

l. Cr

         Variable valencies

a. Cu ¹⁺

b. Cu

c. Hg ¹⁺

d. Hg

e. Fe ²⁺

f. Fe

g. Mn ²⁺

h. Mn

i. Pb ²⁺

j. Pb 

k. Pt ²⁺

l. Pt 

Electro negative ions radicals

Symbols/valency                Name

a. Cl ¹⁻                                Chloride

b. ClO₃

c. ClO

d. Br

e. I

f. OH

g. NO₂

h. NO₃

i. HCO₃

j. HSO₃

k. HSO₄

l. AlO₂

m. MnO₄

n. SO₃

o. SO₄

p. S

q. CO₃

r. O

s. CrO₄

t. Cr₂O₇

u. ZnO₂

v. PbO₂

w. PO₄

x. N

y. C

5) State the valency of each of the elements in the respective compounds in the following:

                                          

a) Sulphur in i) sulphur dioxide

                       ii) sulphur trioxide

b)Nitrogen in i)nitrogen monoxide 

                        ii) Nitrogen dioxide

                        iii) dinitrogen oxide

                    iv) dinitrogen pentoxide

c) copper in i) cupric oxide

                     ii) cuprous oxide

6) complete the following::

 The first example has been completed for you...

1. Cr³⁺        SO²⁻ 

= Cr₂          SO₄ ₃ 

= Cr₂(SO₄)₃

2. Mg     Cl

3. Na      ClO₃ 

4. K         ZnO₂

5. Ca      PO₄ 

6. NH₄     SO₄

7. Na       HSO₃ 

8. Al         S

 

9. Zn        SO₄ 

10. Mg         O 

7) Give the formulas of the following compounds whose metallic radicals exhibits variable valency.

 Compound formula

a. cupric nitrate 

b. cuprous chloride 

c. Iron(II) sulphate 

d. Mercuric nitrate

e. Plumbous chloride

f. Stannous chloride

g. Manganese sulphate

h. Platinic chloride

I. Mercurous chloride

j. Iron(III) nitrate

8) Give the names of the compounds whose formulas listed below.

formula name of the compound

a. HNO₂ 

b. HCO₃ 

c. H₂C₂O₄

d. H₃PO₄

e. CH₃COOH 

f. CaSiO₃ 

g. Na₂ZnO₂ 

h. K₂CrO₄

I. Mg₃N₂ 

9) A chemical equation is a shorthand form for a chemical change

a) 2KClO₃ ∆ -----> 2KCl + 3O₂ 

  i) in the above reaction name the reactant and the products.

 ii) State what the arrow in between indicates.

 

10) GIVE REASON 

a) all equations must be balanced.

b) A chemical equation provides Useful information about a reaction.

c) all chemical equations have their limitations.

11) Balancing of equations is carried out by trial and error method. A simple step-by-step balancing is achieved by taking into account the atoms of the same elements of the reactants with the concerned elements of the products.

 Balance the following equation in a step-by-step manner...

a) CuO + NH₃ ---> Cu+ H₂O + N₂ 

b) NH₃+ Cl₂ --> HCl + NCl₃ 

c) Mg₃N₂+ H₂O --->Mg(OH)₂ +NH₃

d) Pb₃O₄ +HCl---> PbCl₂+H₂O+ Cl₂ 

12) Write the balanced equations for the following word equations:

a) Manganese(IV) oxide + Hydrochloric acid --> manganese(II) chloride +water+ chlorine.

b) Potassium Hydroxide + Chlorine --> Potassium Chloride+ potassium hypochlorite + water

c) ammonium dichromate --> chromium oxide+ water+ nitrogen

d) potassium sulphide + nitric acid--> potassium nitrate +water + Sulphur Dioxide

e) iron(III) chloride +water+ Sulphur Dioxide---> iron(II) chloride+ sulphuric acid+ hydrochloric acid 

f) copper +sulphuric acid--> copper sulphate +water+ Sulphur dioxide.

g) iron(III)oxide +carbon monoxide--> iron+ carbon dioxide.

h) sodium sulphite +sulphuric acid--> sodium sulphate+ water+ Sulphur Dioxide.

I) Zinc+ Sodium Hydroxide--> Sodium zincate + hydrogen

j) aluminium +carbon dioxide--> Aluminium oxide+ carbon

k) sodium bicarbonate+ Aluminium Sulphate -->sodium sulphate +Ammonium hydroxide+ carbon dioxide.

l) calcium hydroxide +Ammonium Sulphate -->calcium sulphate +water+ ammonia

m) nitric acid +magnesium carbonate -->magnesium nitrate + water +carbon dioxide

n) iron(III) oxide+ sulphuric acid --> iron(III) sulphate+ water

o) zinc sulphide+ oxygen--> zinc oxide +Sulphur dioxide.

p) carbon+ nitric acid ---> carbon dioxide + water +Nitrogen dioxide

13) Match the different types of chemical reactions in column II with the meanings of the type of reaction in column I

COLUMN I

a) chemical reaction in which two or more elements or compounds react to form one new compound as a product.

b) A chemical reaction in which a chemical compound decomposes or splits up into two or more simpler substances. It is generally brought about by heat.

c) A chemical reaction which takes place when an element( Or radical) has replaced another element in a compound.

d) A chemical reaction in which two reactants are both decomposed to form new substances by exchanging their radicals.

e) A chemical reaction which employs a catalyst to alter the rate of reaction.

f) A chemical reaction in which the products formed the react together to form the original reactant depending on the conditions of the reaction.

g) A reaction in which a substance dissociates into two or more simpler substances on application of heat and reversible reaction.

h) a reaction which involves addition of oxygen or electronegative element or removal of hydrogen or electropositive element.

I) A reaction which involves of hydrogen or electropositive element or oxygen or removal of oxygen or electronegative element.

j) A chemical reaction which proceeds with evolution of heat energy.

k) A chemical reaction which proceeds with the absorption of heat energy.

l) A chemical reaction which proceeds with absorption of light energy.

COLUMN II

 i) Double decomposition 

ii) exothermic reaction 

iii) reversible reaction

iv) displacement reaction

v) combination or synthesis

vi) decomposition reaction

vii) thermal dissociation

viii) endothermic reaction

ix) catalytic reaction

x) Oxidation reaction

xi) photochemical reaction

xii) reduction reaction 

14) State the type of reaction/s to which each of the following belong.

a) Addition of zinc to copper sulphate solution.

b) Heat on lead nitrate crystals.

c) preparation of oxygen from potassium chlorate

d) conversion of ferrous chloride to ferric chloride using chlorine.

e) formation of ammonia from nitrogen and hydrogen.

f) Liberation of hydrogen at the cathode from acidified water.

g) manufacture of glucose by Green plants.

h) formation of nitric oxide from nitrogen and oxygen

I) addition of zinc to dilute sulphuric acid.

j) NH₄Cl <=> NH₃+HCl

k) 2KNO₃ ∆+ 2KNO₂+ O₂

          

                H₃PO₄

l) 2H₂ ------------->2H₂O+ O₂ 

m) PbBr₂ --> Pb²⁺ + 2Br¹⁻ (ions)

n) 2HgO ∆+ 2Hg + O₂

o) N₂O₄ ∆ <=> 2NO₂ 

p) AgNO₃ + KCl --> AgCl +KNO₃

q) Fe + S --> FeS

                  sunlight

r) H₂+ Cl ₂ -------------> 2HCl

s) C + H₂O --> CO + H ₂ - ∆

t) Cl₂+ 2KI --> 2KCl + I₂

    

                           ∆

u) 3Fe + 4H₂O <=> Fe₃O₄+ 4H₂

v) 2Cu+ O₂ --> 2CuO

w) Fe₂O₃ + 2AI --> Al₂O₃+ 2Fe

x) KNO₃+ H₂SO₄---> HNO₃+KHSO₄ 

y) 2FeCl₂ + Cl₂ ---> 2FeCl₃

z) Fe + H₂SO₄ ---> FeSO₄ + H₂

a') SO₂ + Cl₂ --> SO₂Cl₂ 

b') 3Ca + N₂ ---> Ca₃N₂ 

c') CuSO₄ + Fe --> FeSO₄+ Cu

d') 4HNO₃ --> 2H₂O + 4NO₂ + O₂

15) Find the OXIDATION and REDUCTION reaction as well as REDOX REACTION also find Oxidising AGENT and Reducing AGENT :::

a) Cu+ O₂--> 2CuO

b) CuO+ H₂--> Cu+ H₂O

c) H₂S+ Cl₂ --> S + 2HCl

d) Br₂+ H₂S ---> 2HBr + S

e) 2FeCl₂ + CI₂--> 2FeCl₃

f) 2FeCl₃+H₂S --> 2FeCl₂+ 2HCl+S

g) SO₂+ H₂O + Cl₂ --> H₂SO₄+2HCl

h) 2HgCl₂+SnCl₂ --> HgCl₂+ SnCl₂

i) H₂S+ 2FeCl₃--> 2FeCl₂+2HCl+S

j) 2FeCl₃+ SO₂+2H₂O--> 2FeCl₂++2HCl + H₂SO₄

k) Zn + H₂SO₄--> ZnSO₄+ H₂

l) Fe₂(SO₄)₃+2H₂O+ SO₂--> 2Fe₂SO₄ + 2H₂SO₄

m) Fe + S --> FeS

n)Cl₂+2H₂O+SO₂--> 2HCl+H₂SO₄

   

o) 2Mg+ SO₂ --> 2MgO +S

p) 2HNO₃ +SO₂--> 2NO₂+H₂SO₄

q) 2H₂S + SO₂ --> 2H₂O

r) 2KMnO₄ +5SO₂--> 2NMnSo₄ + K₂SO₄ + 2H₂SO₄

s) S + 2H₂SO₄--> 3SO₂ +2H₂O

t) K₂Cr₂O₇+H₂SO₄+ 3SO₂--> Cr₂(SO₄)₃+ K₂SO₄ +H₂O

16) Name the following::

a) a coloured gaseous oxidising agent.

b) A liquid oxidizing agent which on thermal decomposition in presence of a catalyst liberates oxygen.

c) a gaseous reducing agent containing oxygen.

d) An acid other than nitric and Sulphuric Acid which is an oxidising agent.

e) A gaseous reducing agent neutral in nature other than carbon monoxide.

f) an oxidising agent which liberates chlorine on heating with concentrated hydrochloric acid.

g) two neutral Gases which react to give a basic and the reaction is exothermic.

h) two neutral gases which react to give a neutral oxide and the reaction is exothermic.

I) A substance which decomposes by absorption of sound energy.

j) two substances which react explosively on close physical contact.