Question

Choose the correct answer from the alternative given.
Match the column I with column II and mark the appropriate choice.

	Column I		Column II
(A)	Element with highest second ionisation enthalpy	(i)	Cr
(B)	Element with highest third ionisation enthalpy	(ii)	Cu
(C)	M in $M(CO{)}_6$ is	(iii)	Zn
(D)	Element with the highest heat of atomisation	(iv)	Ni

• A. (A) - (ii), (B) - (iii), (C) - (i), (D) - (iv)
• B. (A) - (iv), (B) - (iii), (C) - (i), (D) - (ii)
• C. (A) - (iii), (B) - (i), (C) - (ii), (D) - (iv)
• D. (A) - (i), (B) - (ii), (C) - (iii), (D) - (iv)

Answer 1

The correct option is A (A) - (ii), (B) - (iii), (C) - (i), (D) - (iv)

Electronic configuration of given elements are:

Cr-[Ar] $3d^{5}4s^1$

Cu-[Ar] $3d^{10}4s^1$

Zn-[Ar] $3d^{10}4s^2$

Ni-[Ar] $3d^{8}4s^2$

Second ionisation enthalpy will be highest in Cu because after losing $1e^{-}$, it will attain a fully filled stable configuration.

Third ionisation enthalpy will be highest in Zn because after losing $2e^{-}$ s, it will attain fully filled d-orbital configuration which is quite stable.

Ni has the highest heat of atomization in the 3d transition series.

Element with the highest heat of atomisation among given is Ni.