Question

A certain compound X imparts a golden yellow flame. When zinc powder is heated with concentrated solution. Of X, $H_{2}$gas is evolved. X combines with $CO_{2}$ to give a salt Y. Y is a hydrated salt which on reaction with HCl or excess of $CO_{2}$ gives another salt Z which is an important part of baking powder. Identify X, Y and Z.

	X		Y			Z

• A. | NaOH | | $Na_{2}CO_{3}$ | | | $NaHCO_{3}$ | | |
• B. | HCl | | NaOH | | | $NaHCO_{3}$ | | |
• C. | KOH | | $K_{2}CO_{3}$ | | | $KHCO_{3}$ | | |
• D. | NaCl | | $Na_{2}CO_{3}$ | | | NaOH | | |

Answer 1

: $Zn + \underset{(X)}{2NaOH} \rightarrow Na_{2}ZnO_{2} + H_{2}$

$\underset{(X)}{2NaOH} + CO_{2} \rightarrow \underset{(Y)}{Na_{2}CO_{3}} + H_{2}O$

$\underset{(Y)}{Na_{2}CO_{3}} + HCl \rightarrow \underset{(Z)}{NaHCO_{3}} + NaCl$

$\underset{(Y)}{Na_{2}CO_{3}} + CO_{2} + H_{2}O \rightarrow \underset{(Z)}{2NaHCO_{3}}$