(Mendeleeff, Robert Boyle, Early chemists, Newland, Lavoisier , Dobernier, Carl Scheele, Moseley, Humphry Davy)
a) _____ attempted to classify elements on basis of their properties, metallic and non-metallic nature, valency etc, but the classification was discarded and atomic weight and not properties were considered for further classification.
b) _____classified elements into groups of three on observing a relationship between atomic weights of certain elements and their properties. He arranged elements in increasing order of atomic weights in group of three called triads.
c) ____ arranged elements in series in ascending order of their atomic weights and suggested a resemblance between the eighth and first element similar to the eighth and first notes on a musical scale.
d) _____ arranged elements in increasing order of their atomic weights and observed that elements with similar propertie appear at regular intervals on arrao. Such properties are called periodic properties and are those which appear at regular intervals in a periodic table. Examples such that properties are valency, electronegativity, metallic and non-metallic character .
e) _____stated that atomic number and non atomic weight of an element should be taken into consideration for classification of elements.
f) ______ periodic laws states that the physical and the chemical properties of elements are periodic functions of their atomic weights.
g) ____ arranged elements in increasing order of the atomic numbers in seven horizontal rows called periods and eighteen vertical columns called groups.
2) State the following with respect to table A and table B -- pertaining to classification of elements by different scientists .
b) State the law which pertains to classification of elements are seen in table A .
c) Name the scientist whose law pertains to classification of elements as seen in table B.
d) State the law which pertains to classification of elements as seen table B.
3) Give reasons for the following:
a) Classification of elements by early chemists on basis of properties, valencies and metallic and nonmetallic nature of elements was soon discarded.
b) Dobernier's Law of traids did not hold weightage as a standard for classification for all elements.
c) Newland's classification of elements led to much criticism.
4) Mendeleeff's Periodic Table
Answer the following with reference to mendeleeff's periodic table.
a) On what basis was the above classification of elements made by Mendeleeff.
b) State the terms used for the following pertaining to Mendeleeff's periodic table.
i) The horizontal rows of elements in the predic table.
ii) The vertical columns of the elements in the periodic table.
iii) The properties which repeat themselves at regular intervals in the periodic table
c) State three contributions made by Mendeleeff which significantly helped to form the basis of the Modern Periodic Table.
d) Give reasons why Mendeleeff's Periodic Table was not completely accepted as the Modern Periodic Table.
5) FROM THE MODERN OR LONG FORM OF THE PERIODIC TABLE :
Answer the followings:
Name or state the following pertaining to the Modern Periodic Table .
a) The fundamental characteristics of an element which formed the basis of classification of elements in the Modern Periodic Table.
b) The number of horizontal rows - periods in the table.
c) The number of vertical columns - groups in the table.
d) The period which contains only two elements.
e) The periods which contains 8 elements.
f) The period which contains the element having table electronic configuration 2,8,8.
g) The first elements of the periodic table.
h) The type of elements present the zero group of the periodic table.
i) The last element of the third short period.
j) The period which contains thelanthanide series which is situated at the bottom of the periodic table.
k) The groups which are further divided into sub-groups A and B .
6) Name or state the following pertaining to the elements of the periodic table.
a) The number of electron shells in the elements of periods 1, 2 or 3 respectively.
b) The electronic configuration of the zero group element period-1.
c) The number of valence electrons of the element in group IV of period-2 of the periodic table.
d) The valency of the elements of group I A, VIIA and zero group.
e) The group to which the elements carbon (at.no.6), nitrogen (at.no.7) and oxygen (at.no 8) belong.
f) The period to which sulphur (at.no 16) and chlorine (at.no 17) belong.
g) The electronegativite element from the elements sodium, magnesium and sulphur.
h) The type of bonding seen in the oxide of the element in periodic-3, group III A.
i) An element in period-3, group VA whose chloride exists in two different physical states.
j) The groups of the periodic table which contains the alkali metals , alkaline earth metals and the halogens respectively.
k) The grouping name given to the type of the elements present in groups
a) I B to VIIB and VIII
b) I A to VIIA.
l) The non-metal positioned in group I A.
m) The series of chemically reactive metals of period -7 placed at the bottom of the periodic table.
n) The least electronegative elements from the elements chlorine, bromine and iodine in group VIIA.
o) The elements in period-2, group I A, which shows similarity with a divalit metal in period -3 group II A.
p) The non-metallic element in period-2 which is diatomic and unreactivate at ordinary temperatures.
7) State whether the following statements are true or false if false rewrite the correct statement.
a) Elements with similar outer electronic configurations are placed in the same period of the periodic table.
b) If properties of one member of a group is known, the properties of other members of the group could be correlated due to similarity or gradation in properties of elements in a group.
c) Non-metals occupy the upper right hand corner of the periodic table.
d) The two sub-groups A and B accommodate elements with similar properties.
e) Properties of elements remain the same on moving from left to right in the modern period table .
f) Electronegativity and non-metallic character of elements increases across a period from left to right and decreases down a group.
8) Complete the statements given below by filling in the correct word in the blank from the word/s in bracket.
a) The periodic table is based on the basis fundamental property____(atomic weight/atomic number/electronic configuration).
b) Elements arranged in increasing order of atomic___ (numbers/weights).
c) _____horizontal rows called_____ (5/7/18/periods /groups).
d) ____ vertical columns called____(6/8/18/periods /groups)
e) Transition from____ to ____character across a period.(Metallic/non-metallic)
f) Groups ____to____ sub-divided into A and B. (I/II/VI/VII)
g) Grour____to_____are called 'Normal'- 'representative elements'.(IIA/IIA/VIA/VIIA)
h) Group____ to_____and____ are called 'Transition Elements' .(IB/VIB/VIIB/VIII)
i) Group____ at extreme___ contains 'noble gases'. (IA/0/VIIA/right/ left)
j) _____elements placed in group IA & IIA. (reactive, metallic/ reactive, nonmetallic)
k) ______ elements placed in the upper right hand corner.(non-metallic/ metallic)
l) Periodicity in properties i.e., recurrence in properties are seen with elements belonging to the same____(period/group/sub-group ) in the periodic table after a difference of ___, ____, ____, or ____. (18/2/32/8) in atomic number due to recurrence of similar_____(atomic weights/number of shells/valence electronic configuration)
m) Alkali metals Li, Na are present in group _____. (IB/IA/IIA)
n) Alkaline earth metals Be, Mg are present in group____. (IA/IIA/IVA)
o) Post-transition metal - Al is present in group ____.(IIA/IIIA/VIA)
p) Transition metal - Fe is present in group____(VIIB/VIII/IB)
q) Transition metal - Zn is present in group _____(IB/IIB/IIIB)
r) Lanthanide series are present in period______(2/3/6/7)
s) Actinide series are present in period _______(2/3/6/7)
9) Name or state the following pertaining to elements of the first three periods:
a) The number of electron shells in period-1, 2 and 3 respectively.
b) The period number of the element 'X' having electronic configuration 2, 8, 8, 1.
c) The number of elements in the shortest period.
d) The number of short periods of the periodic table.
e) The metallic elements in period-2 and period-3.
f) The non-metallic elements in period-2 and period-3.
g) The element in period-2 and the period-3 having stable electronic configuration.
h) The elements in period-3 having 5 valence electrons.
i) The element in period-2 having electronic configuration 2, 4.
j) The period/s having 8 elements.
k) The element having one shell and one valence electron.
l) The period containing
i) rare Earth elements
ii) radioactive elements.
m) The bridge element in period-2 which has a diagonal relationship with aluminium in period-3.
n) A metalloid in period-3 0.
o) The valency of the elements in period-2
i) group- V
ii) group 0.
p) The type of bonding of the chloride of the element in period-3 , group IIA.
q) The state of the chloride of the elements in period-3 group VIA.
r) Two property trends of elements which increse from left to right in a period.
10) Name of state the following pertaining to elements in group of the periodic table.
a) The number of valence electrons of the elements in group I A and in IIA.
b) The group number of the group having three columns of elements.
c) The group number to which lithium and sodium belong.
d) The group member to which magnesium and calcium belong.
e) The group number to which elements with 7 valence electrons belongs.
f) The type of elements present in group IB to VIIB & VIII.
g) The group to which inert , unreactive elements belong.
h) The group to which the most reactive metals belong.
i) The two property trends which remain same or similar down a sub-group.
11) Complete the table pertaining to Periodicity of elements by selecting the correct term/s in each case.
a) The Modern Periodic Table Law states that properties of elements are periodic functions of their____( atomic mass/molecular mass/ atomic numbers)
b) The properties which reappear at regular intervals in the periodic table are called______(atomic/period/ periodic properties )
c) _____is one of the periodic properties, predict in nature. (electronic configuration/ atomic radius/ electroni pull)
d) An element is said to be a _____ if it loses one or more electrons when supplied with energy. ( non-metal/ metal/ metalloid)
e) A_____is formed from a metal by loss of electrons.(Anions/cation/proton)
f) An elements 'X' an electron when supplied with energy. The electronic configuration of X is_____( 2, 8/2, 8, 1/2, 8, 7)
g) An element 'Y' has atomic number seven and mass number fourteen. It's neutron/proton(n/p) ratio is ____(3/1.5/1)
h) In the same period or sub-group, increase or decrease in a particular(periodic ) property is due to gradual charge in _____.(atomic weight /atomic size/ electronic configuration) in the arranged elements.
12) Select the correct element in each case.
a) Select the element which show metallic character:- Na, Al, Si, P
b) Select the elements which show non-metallic character- Be, C, Li, Cl
c) Select the elements which show metalloid characters:- Be, B, C, N, F, Si
d) Select the elements which have three electron shells - Li, B, Al, S
e) Select the element which has the common valency 3 - Li, Be, B, C, Al
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