Question

A compound X is formed when carbon dioxide reacts with sodium hydroxide. The same compound is obtained when baking soda is heated. Identify X.

• A. $N{a}_{2}O$
• B. $N{a}_{2}C{O}_3$
• C. $NaCl$
• D. $NaOH$

Answer 1

The correct option is B $N{a}_{2}C{O}_3$

Sodium hydroxide reacts with carbon dioxide to produce sodium carbonate $\left(N{a}_{2}C{O}_3\right)$.

$2\mathrm{NaOH}\left(\mathrm{aq}\right)+{\mathrm{CO}}_2\left(g\right)\to {\mathrm{Na}}_2{\mathrm{CO}}_3\left(\mathrm{aq}\right)+H_{2}O\left(l\right)\mathrm{Sodium}\mathrm{Carbon}\mathrm{Sodium}\mathrm{Water}\mathrm{hydroxide}\mathrm{dioxide}\mathrm{carbonate}$

It can also be obtained by heating baking soda $\left(NaHC{O}_3\right)$.
$2{\mathrm{NaHCO}}_3\left(\mathrm{aq}\right)\stackrel{\Delta }{\to }{\mathrm{Na}}_2{\mathrm{CO}}_3\left(\mathrm{aq}\right)+{\mathrm{CO}}_2\left(g\right)+H_{2}O\left(l\right)\mathrm{Sodium}\mathrm{Sodium}\mathrm{Carbon}\mathrm{Water}\mathrm{bicarbonate}\mathrm{carbonate}\mathrm{dioxide}$

Hence, the compound X is sodium carbonate $\left(N{a}_{2}C{O}_3\right)$.