Đáp án đúng: D
H2SO4 đặc + Cu
$\begin{array}{l}{{H}_{2}}S{{O}_{4}}+CuO\xrightarrow{{}}CuS{{O}_{4}}+{{H}_{2}}O\\\,\,\,\,a\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\to \,\,\,\,\,\,\,\,\,\,\,\,\,a\\{{H}_{2}}S{{O}_{4}}+Cu{{(OH)}_{2}}\xrightarrow{{}}CuS{{O}_{4}}+2{{H}_{2}}O\\\,\,\,\,a\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\to \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,a\\{{H}_{2}}S{{O}_{4}}+CuC{{O}_{3}}\xrightarrow{{}}CuS{{O}_{4}}+{{H}_{2}}O+C{{O}_{2}}\\\,\,\,\,a\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\to \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,a\\2{{H}_{2}}S{{O}_{4(d)}}+Cu\xrightarrow{{}}CuS{{O}_{4}}+S{{O}_{2}}+2{{H}_{2}}O\\\,\,\,\,\,a\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\to \,\,\,\,\,\,\,\,\,\,\,\,\,\,\frac{a}{2}\end{array}$
