Question

Oh! We are nearly there. You can almost smell copper. Molten Copper Matte is then transferred to a Bessemer converter where it undergoes___reduction

Answer 1

In the converter, $C{u}_{2}S$ is converted to $C{u}_{2}O$ and the following happens

$C{u}_{2}S+2C{u}_{2}O\to 3Cu\left(I\right)+S{O}_2\uparrow$

Sometimes, due to the blast of hot air in the converter $C{u}_{2}S$ is oxidized to $CuS{O}_4$, which then undergoes:

$CuS{O}_4+C{u}_{2}S\to 3Cu\left(I\right)+2S{O}_2\uparrow$