Q. The atomic number of elements $A$, $B$, $C$ and $D$ are $Z - 1$, $Z + 1$, and $Z + 2$, respectively. If ‘$B$’ is a noble gas, choose the correct answer from the following statements. ‘$A$’ has higher electron affinity ‘$C’\$exists in +2 oxidation state ‘$D’\$is an alkaline earth metal
A) I and II
B) II and III
C) I and III
D) I, II and III
Explanation
(c)
Given,
Atomic number of element $B = Z$
$(\because Noble\ gas\ \therefore Belong\ to\ zero\ group)$
Atomic number of element $A = Z - 1$
(i.e., halogens)
Atomic number of element $C = Z + 1$
(i.e., group IA)
Atomic number of element $D = Z + 2$
(i.e., group II A)
$\because$ Element B is a noble gas.
$\therefore$ Element $A$ must be a halogen i.e., have highest electron affinity and element $C\$must be an alkali metal and exist in+1 oxidation state.
And element $D$ must be an alkaline earth metal with +2 oxidation state.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.