When white phosphorus reacts with caustic soda,$PH_3$ and $NaH_2PO_2$ are produced. This reaction is an example of what?

In the reaction $P + NaOH \to PH_3 + NaH_2PO_2$

Ammonium dichromate on heating gives:

Which one of the following is a disproportionation reaction?

The reaction of white phosphorus with aqueous $NaOH$ gives phosphine along with another phosphorus-containing compound. The reaction type and the oxidation states of phosphorus in phosphine and the other product are respectively:

Assign $A, B, C, D$ from the given type of reaction.
$Na_2C_2O_4 + H_2SO_4 \text{ (conc.)} \longrightarrow Na_2SO_4 + CO + CO_2$