Question

Calcium burns in nitrogen to produce a white powder which dissolves in sufficient water to produce a gas (A) and an alkaline solution. The solution on exposure to air produces a thin solid layer of (B) on the surface.

When $C{O}_2$ gas passed into the alkaline solution, then which of the following product will be formed?

• A. $BaC{O}_3$
• B. $CaC{O}_3$
• C. $SrC{O}_3$
• D. None of these

Answer 1

The correct option is B $CaC{O}_3$

Calcium burns in nitrogen to produce a white powder
$3Ca+N_2\to C{a}_3{N}_2$ (white powder which dissolves in sufficient water to produce a gas (A))

$C{a}_3{N}_2+6H_{2}O\to 3Ca(OH{)}_2+2N{H}_3$. So, the gas A would be $N{H}_3$ and alkaline solution would be $Ca(OH{)}_2$.

The solution on exposure to carbon dioxide produces a thin solid layer of (B) on the surface.

$Ca(OH{)}_2+C{O}_2\to CaC{O}_3+H_{2}O$.

So the thin layer B would be $CaC{O}_3$. So, B is $CaC{O}_3$
Hence, option B is correct.