The metal-pair that can produce nascent hydrogen in alkaline medium is

$A$ metal $X$ on heating in a stream of nitrogen gives $Y$. $Y$ on reaction with ${H_2}O$ gives a colorless gas which,when passed through a $CuSO_4$ solution,gives a blue color. What is $Y$?

Four reactions are given below:
$(i)$ $2Li + 2H_2O \to 2LiOH + H_2$
$(ii)$ $2Na + 2H_2O \to 2NaOH + H_2$
$(iii)$ $2LiNO_3 \xrightarrow{\text{Heat}} 2LiNO_2 + O_2$
$(iv)$ $2NaNO_3 \xrightarrow{\text{Heat}} 2NaNO_2 + O_2$
Which of the above,if any,is wrong?

The $INCORRECT$ statement is:

Glauber's salt is

Identify the incorrect statement from the following.