JEE Main Previous Year Papers Questions With Solutions Chemistry Periodic Classification and Properties

JEE Main Previous Year Papers Questions With Solutions Chemistry Periodic Classification and Properties

1.Which is the correct order of ionic sizes ?(2002)
(1)Ce > Sn > Yb > Lu 2) Sn > Ce > Cu > Yb
3) Lu > Yb > Sn > Ce     4) Sn > Yb > Ce > Lu
Ans.(1) Size decrease as Z increases.

2.The radhis of La³⁺ (Atomic number of La=57) is 1.06A. Which one of the following given values will be closest to the radius of Lu³⁺ (Atomic number of Lu = 71)?          (2003)
(1)40 A     2) 1.06 A
3) 0.85 A   4) 1.60 A
Ans.

3.According to the Periodic Law of elements, the variation in properties of elements is related to their.        (2003)
(1)nuclear masses
(2) atomic numbers
(3)nuclear neutron-proton number ratios
(4)atomic masses
Ans.(2)The properties of elements change with a change in atomic number

4.Which one of the following is an amphoteric oxide?              (2003)
(1)Na₂0 2) S0₂  3)B₂0₃          4) ZnO
Ans.(4) ZnO reacts with HC/ and NaOH

5.The atomic numbers of vanadium (V),Chromium (Cr), manganese (Mn) and iron (Fe) are respectively 23, 24, 25 and 26. Which one of these may be expected to have the highest second ionization enthalpy ? (2003)
(1)C r 2) Mn         3) Fe            4) V
Ans.

Ans.

Ans.(1)18 electrons each.

8.Among A1₂0₃, Si0₂, P₂0₃ and S0₂ the correct order of acid strength is                      (2004)(1)S0₂ < P₂0₃ < Si0₂ < A1₂0₃
(2)A1₂0₃ < Si0₂ < P₂0₃ < S0₂
(3)A1₂0₃ < Si0₂ < S0₂ < P₂0₃
(4)Si0₂ < S0₂ < A1₂0₃ < P₂0₃
Ans.(2)Al, Si, P, S. Acidity of oxides increases with increase in non-metallic character.

Ans.

10.Beryllium and aluminium exhibit many properties which are similar. But the two elements differ in    (2004)
(1)exhibiting maximum covalency in compound
(2)exhibiting amphoteric nature in their oxides
(3)forming covalent halides
(4)forming polymeric hydrides
Ans. (1)Be and Al have diagonal relationship. They possess similar properties but Be cannot form they polymeric hydrides.

11.Which of the following oxides is amphoteric in character ?                        (2005)
(1)CaO 2) C0₂ 3) Si0₂ 4) Sn0₂
Ans.

12.The lanthanide contraction is responsible for the fact that                             (2005)
(1)and Y have about the same radius
(2)Zr and Nb have similar oxidation state
(3)Zr and Hf have about the same radius
(4)Zr and Zn have the same oxidation
Ans.(3) Due to Lanthanide contraction.

13.In which of the following arrangements the order is NOT according to the property indicated against it   ?          (2005)
(1)Al³⁺ < Mg²⁺ < Na⁺ < F”
‘ Increasing ionic size
(2)B<C<N<0 ‘
Increasing first ionization enthalpy
(3)I < Br < F < Cl
Increasing electron gain enthalpy
(4)Li < Na < K < Rb Increasing metallic radius
Ans.(2) Ionisation energy of N is more (p³ config) B < C < O < N

14..Which of the following factors may be regarded as the main cause of lanthanide contraction ?(2005)
(1)Poor shielding of one of 4f electron by another in the subshell
(2)Effective shielding of one of 4f electrons by another in the subshell
(3)Poorer shielding of 5d electrons by 4f electrons
(4)Greater shielding of 5d electrons by 4f electrons
Ans.(1) Poor shielding of f electrons.

15.Which one of the following sets of ions represents a collection of isoelectronic species?            (2006)
1) K⁺ , Cl”, Ca²⁺, Sc³⁺ 2) Ba²⁺, Sr²⁺, K⁺, S²“
3) N³-, O²-, F”, S²–          4) Li⁺, Na⁺, Mg²⁺, Ca²⁺
Ans.(1) Each species with 18 electrons

16.The increasing order of the first ionization enthalpies of the elements B, P, S and F (lowest first) is            (2006)
1)F<S<P<B        2)P<S<B<F
3)B<P<S<F        4)B<S<P<F
Ans.(4) B has lone p’ electron.

17.Following statements regarding the periodic trends of chemical reactivity of the alkali metals and the halogens are given. Which of these statements gives the correct picture?(2006)
(1)The reactivity decreases in the alkali metals but increases in the halogens with increase in atomic nu’mber down the group
(2)In both the alkali metals and the halogens the chemical reactivity decreases with increase in atomic number down the group
(3)Chemical reactivity increases with increase in atomic number down the group in both the alkali metals and halogens
(4)In alkali metals the reactivity increases but in the halogens it decreases with increase in atomic number down the group
Ans.(4) Most reactive metal is Cs and most reactive non metal is F.

18.The charge/size ratio of a cation determines its polarizing power. Which one of the follow­ing sequences represents the increasing order of the polarizinig order of the polarizing power of the cationic species, K⁺, Ca²⁺, Mg²⁺, Be²⁺ ? (2007)
(1)Mg²⁺,Be²⁺,K⁺,Ca²⁺
(2)Be²⁺, K⁺, Ca²⁺, Mg²⁺
(3)K⁺,Ca²⁺,Mg²⁺,Be²⁺
(4)Ca²⁺,Mg²⁺,Be²⁺,K⁺
Ans.(3) Higher the charge / size ratio, more is the polarizing power.

19.The set representing the correct order of ionic radius is :    (2009)
(1)Li⁺ > Be²⁺ > Na⁺ > Mg²⁺
(2)Na⁺ > Li⁺ > Mg²⁺> Be²⁺
(3)Li⁺ > Na⁺ > Mg²⁺ > Be²⁺
(4)Mg²⁺ > Be²⁺ > Li⁺ > Na⁺
Ans.(2) Follow the periodic trends of ionic radii

20.The correct order of radii is (2010)
(1)Al³⁺ > Mg²⁺ > Na⁺ > F- > O²–
(2)Na⁺ > Mg²⁺ > Al³⁺ > O²– > F^–
(3)Na⁺ > F- > Mg²⁺ > O²– > Al³⁺
(4)O²– > F- > Na⁺ > Mg²⁺ > Al³⁺
Ans.

21.Which one of the following orders presents the correct sequence of the increasing basic nature of the given oxides ?       (2011)
(1)IS^O < I^O < MgO < A/₂0₃
(2)I^O < Na₂0 < A/₂0₃ < MgO
(3)A/₂0₃ < MgO < NajO < K^O
(4)MgO < K^O < AZ₂0₃ < Na₂0
Ans.(3) As electropositive character increases basic nature metal oxides increases
A/₂0₃< MgO < Na_zO < K₂0

22.Iron exhibits +2 and +3 oxidation states.Which of the following statements about iron is incorrect ?    (2012)
(1)Ferrous oxide is more basic in nature than the ferric oxide
(2)Ferous compounds are relatively more ionic than the corresponding ferric compounds
(3)Ferrous compounds are less volatile than the corresponding ferric compounds
(4)Ferrous compounds are more easily hydrolysed than the corresponding ferric compounds
Ans.(4) With increasing the oxidation state, acidic strength increases. Basic strength : FeO > Fe₂0₃ With increasing the positive charge of cation, ionic nature decreases. Thus ferrous compounds are more ionic than ferric compounds.Ferrous compounds are less easily hydrolysed than ferric compounds.

Ans.

24.Which of the following represents the correct ‘ order of increasing first ionization enthalpy for Ca, Ba, S, Se and Ar ?                   (2013)
(1)Ca< S < Ba < Se < Ar
(2)S < Se < Ca < Ba < Ar
(3)Ba < Ca < Se < S < Ar
(4)Ca < Ba < S < Se < Ar
Ans.(3) First ionisation enthalpy is highest for Ar. Least for Ba

25.The ionic radii (in ) of N respectively
(1)36, 1.40 and 1.71
(2)36, 1.71 and 1.40
(3)71, 1.40 and 1.36
(4)71 and 1.36 and 1.40
Ans.[3] N-³ > CL² > F­In isoelectronic series size decreases as increases.