The first, second and third ionisation energies (E₁, E₂ and E₃) for an element are 7 eV, 12.5 eV and 42.5 eV respectively. The most stable oxidation state of the element will be:

1. +1

2. +4

3. +3

4. +2

The order of ionisation potential between He⁺ ion and H-atom (both species are in gaseous state) is :

1. I.P(He⁺ ) = I.P (H)

2. I.P(He⁺ ) < I.P (H)

3. I.P(He⁺ ) > I.P (H)

4. Cannot be compared

Second ionisation potential of Li, Be and B is in the order:

1. Li > Be > B

2. Li > B > Be

3. Be > Li > B

4. B > Be > Li

Which of the following isoelectronic ion has the lowest ionization energy?

1. K⁺

2. Cl^-

3. Ca²⁺

4. S^2-

Which of the following is arranged in order of increasing radius ?

1. K⁺ (aq) < Na⁺ (aq) < Li⁺(aq)

2. Na⁺(aq) < K⁺ (aq) < Li⁺ (aq)

3. K⁺(aq) < Li⁺(aq) < Na⁺(aq)

4. Li⁺(aq) < Na⁺(aq) < K⁺(aq)

Which of the following processes involves absorption of energy?

1. $\mathrm{S}\left(\mathrm{g}\right)+{\mathrm{e}}^{-}\to {\mathrm{S}}^{-}\left(\mathrm{g}\right)$

2. ${\mathrm{S}}^{-}+{\mathrm{e}}^{-}\to {\mathrm{S}}^{2-}\left(\mathrm{g}\right)$

3. $\mathrm{Cl}\left(\mathrm{g}\right)+{\mathrm{e}}^{-}\to {\mathrm{Cl}}^{-}\left(\mathrm{g}\right)$

4. None of the above

Arrange N, O and S in order of decreasing electron affinity:

1. S > O > N

2. O > S > N

3. N > O > S

4. S > N > O

Arrange the following elements, based on their electron configurations, in increasing order of electron affinity:

(I) $1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{6}3{\mathrm{s}}^{2}3{\mathrm{p}}^5$

(II) $1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^3$

(III) $1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^5$

(IV) $1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{6}3{\mathrm{s}}^1$

1. II < IV < III < I

2. I < II < III < IV

3. I < III < II < IV

4. IV < III < II < I

The process requiring absorption of energy is:

1.  $\mathrm{N}\to {\mathrm{N}}^{-}$

2. $\mathrm{F}\to {\mathrm{F}}^{-}$

3. $\mathrm{Cl}\to {\mathrm{Cl}}^{-}$

4. $\mathrm{H}\to {\mathrm{H}}^{-}$

Which of the following electronic configuration represents a sudden large gap between the values of second and third ionisation energies of an element?