Magnesium nitrate, $\text{Mg(NO}_3\text{)}_2$, decomposes on heating to form a white solid together with a mixture of gases. One gas given off is a nitrogen oxide, $X$. $7.4\,\text{g}$ of anhydrous magnesium nitrate is heated until the reaction is complete. What mass of $X$ is produced?
- A$1.5\,\text{g}$
- B$2.3\,\text{g}$
- C$3.0\,\text{g}$
- D$4.6\,\text{g}$