Dihydrogen reacts with CuO to give :

Solution

Chemistry ma’am · 3 steps

Dihydrogen is a reducing agent here: it pulls the oxygen off CuO and leaves bare copper metal behind.

1. Role of hydrogen. On heating, H₂ removes oxygen from the oxides of less reactive metals such as copper. The oxygen leaves as water.

   CuO + H₂ →(Δ) Cu + H₂O

2. Track the oxidation state. Copper goes from +2 in CuO to 0 in Cu, so it is reduced. Hydrogen goes from 0 to +1 in H₂O, so it is oxidised. The black CuO turns into reddish-brown copper metal.
3. So. The product is copper metal, option (b).

The idea to keep. Hot H₂ reduces the oxides of metals below it in reactivity, like Cu, Pb and Fe, to the free metal and water. Think of it as oxygen removal, not as hydride or hydroxide formation.

Answer from the NTA final answer key. Solution by PrepWiser.