Question

An atom of one element A has three electrons in its outermost shell, and that of B has six electrons in the outermost orbit. The formula of the compound formed by these two will be :

• A. $A_3{B}_6$
• B. $A_{2}B$
• C. $A_2{B}_3$
• D. $A_3{B}_2$

Answer 1

Answer: (C)

$A_2{B}_3$

B completes its octet by gaining 2 electrons from A and A completes its octet by losing three electrons to B. Thus $A^{+3}$ and $B^{-2}$ ions are formed.

The compound is $A_2{B}_3,e.g.A{l}_2{O}_3.$

So, the correct option is $C$