The disproportionation products of $ortho-phosphorous$ acid are

The reaction $2Cu^{+} \rightarrow Cu + Cu^{2+}$ is called:

Which of the following reactions is a disproportionation reaction?

Refer to the periodic table and answer the following questions:
$(a)$ Select the possible non-metals that can show disproportionation reaction.
$(b)$ Select three metals that can show disproportionation reaction.

$Cu^{+}$ ion is not stable in aqueous solution,because it shows $-$

Fluorine reacts with ice and results in the change: $H_2O_{(s)} + F_{2(g)} \to HF_{(g)} + HOF_{(g)}$. Justify that this reaction is a redox reaction.