Classification of Elements and Periodicity in Properties

Identify the wrong statement in the following.

1. Amongst isoelectronic species, smaller the positive charge on the cation, smaller is the ionic radius.
2. Amongst isoelectronic species, greater the negative charge on the anion, larger is the ionic radius.
3. Atomic radius of the elements increases as one moves down the first group of the periodic table.
4. Atomic radius of the elements decreases as one moves across from left to right in the 2nd period of the periodic table.

What is the value of electron gain enthalpy of Na+ if IE1 of Na = 5.1 eV?

1. -5.1 eV
2. -10.2 eV
3. +2.55 eV
4. +10.2 eV

Which of the following oxide is amphoteric?

1. SnO2
2. CaO
3. SiO2
4. CO2

Among the elements Ca, Mg, P and Cl, the order of increasing atomic radii is

1. Mg < Ca < Cl < P
2. Cl < P < Mg < Ca
3. P < Cl < Ca < Mg
4. Ca < Mg < P < Cl

Among the following which one has the highest cation to anion size ratio?

1. CsI
2. CsF
3. LiF
4. NaF

The correct order of the decreasing ionic radii among the following isoelectronic species is

1. Ca2+ > K+ > S2- > Cl-
2. Cl- > S2- > Ca2+ > K+
3. S2- > Cl- > K+ > Ca2+
4. K+ > Ca2+ > Cl- > S2-

Which of the following represents the correct order of increasing electron gain enthalpy with negative sign for the elements O, S, F and Cl ?

1. Cl < F < O < S
2. O < S < F < Cl
3. F < S < O < Cl
4. S < O < Cl < F

Amongst the elements with following electronic configurations, which one of them may have the highest ionisation energy ?

1. [Ne] 3s2 3p2
2. [Ar] 3d10 4s2 4p3
3. [Ne] 3s2 3p1
4. [Ne] 3s2 3p3

Identify the correct order of the size of the following:

1. Ca2+ < K+ < Ar < Cl- < S2-
2. Ar < Ca2+ < K+ < Cl- < S2-
3. Ca2+ < Ar < K+ < Cl- < S2-
4. Ca2+ < K+ < Ar < S2- < Cl-

With which of the following electronic configuration an atom has the lowest ionisation enthalpy?

1. 1s2 2s2 2p3
2. 1s2 2s2 2p6 3s1
3. 1s2 2s2 2p6
4. 1s2 2s2 2p5