Question

Name the gas produced

i. by the action of dilute nitric acid on copper, and

ii. on heating sodium nitrate.

Answer 1

i. When dilute nitric acid reacts with $\mathrm{Cu}$, then Copper nitrate, Water, and Nitric oxide are formed as a product.

$$\begin{gathered} 3\mathrm{Cu}\left(\mathrm{s}\right)+8{\mathrm{HNO}}_3\left(\mathrm{aq}\right)\to 3\mathrm{Cu}{\left({\mathrm{NO}}_3\right)}_2\left(\mathrm{aq}\right)+2\mathrm{NO}\left(\mathrm{g}\right)+4{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right) \\ \mathrm{Copper}\mathrm{Nitric}\mathrm{Copper}\mathrm{Nitric}\mathrm{Water} \\ \mathrm{acid}\mathrm{nitrate}\mathrm{oxide} \end{gathered}$$

Thus, Nitric oxide gas produced during the reaction of Copper with dilute nitric acid.

ii. On heating the Sodium nitrate, it decomposes to give sodium nitrite and oxygen gas as a products.

$$\begin{gathered} 2{\mathrm{NaNO}}_3\left(\mathrm{s}\right)\stackrel{△}{\to 2}{\mathrm{NaNO}}_2\left(\mathrm{s}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right) \\ \mathrm{Sodium}\mathrm{Sodium}\mathrm{Oxygen} \\ \mathrm{nitrate}\mathrm{nitrite}\mathrm{gas} \end{gathered}$$

Thus, Oxygen gas is produced when we heat the Sodium nitrate.