Question

Periodic Table(Abbreviated): The element that will react in a $1:1$ ratio with (D) is:

• A. A
• B. B
• C. C
• D. D
• E. E

Answer 1

The correct option is B B

The given $1:1$ ratio is shown by $B$ and $D$ elements since $B$ is in group $I$ and has one electron to lose while $D$ with $7$ electrons in valence shell can gain one electron to complete its octet. Thus $B$ and $D$ form compound with formula $BD$.