Question

The ground state electronic configuration of the elements $U,V,W,X$ and $Y$ (these symbols do not have any chemical significance) are as follows:
$U1s^{2}2s^{2}2p^{3}V1s^{2}2s^{2}2p^{6}3s^{1}W1s^{2}2s^2{p}^{6}3s^{2}3p^{2}X1s^{2}2s^2{p}^{6}3s^{2}3p^{6}3d^{5}4s^{2}Y1s^{2}2s^2{p}^{6}3s^{2}3p^{6}3d^{1}04s^{2}4p^6$
Determine which sequence of elements satisfy the following statements:
(i)Element forms a carbonate which is not decomposed by heating
(ii)Element is most likely to form coloured ionic compounds
(iii)Element has largest atomic radius
(iv)Element forms only acidic oxide

• A. $VWYU$
• B. $VXYW$
• C. $VWYX$
• D. $VXWU$

Answer 1

The correct option is B $VXYW$

(i) Alkali metals do not decompose even at red hot $\to$ V.
(ii) Transition metal ions having unapired $d$ electrons are colored in aq. solution/ compounds $\to X$.
(iii) In case of $Kr$ van der Waal's radius is considered, which is largest atomic radius $\to$Y.
(iv) $Si$ atom has only one acid $Si{O}_2\to$ W.