Hydrogen has three isotopes $(A)$,$(B)$ and $(C)$. If the number of neutron$(s)$ in $(A)$,$(B)$ and $(C)$ respectively,are $(x)$,$(y)$ and $(z)$,the sum of $(x)$,$(y)$ and $(z)$ is:

Consider the following sequence of reactions: $Na + NH_{3(g)} \to [X]$ $\xrightarrow{N_2O} [Y]$ $\xrightarrow{\text{Heat}} [Z] (\text{Gas, Pure})$. Identify $[Z]$ gas.

Ortho- and para-hydrogens have

Which of the following statements are $NOT$ correct?
$A$. Hydrogen is used to reduce heavy metal oxides to metals.
$B$. Heavy water is used to study reaction mechanism.
$C$. Hydrogen is used to make saturated fats from oils.
$D$. The $H-H$ bond dissociation enthalpy is lowest as compared to a single bond between two atoms of any elements.
$E$. Hydrogen reduces oxides of metals that are more active than iron.
Choose the most appropriate answer from the options given below:

Calcium imide on hydrolysis gives gas $(B)$ which on oxidation by bleaching powder gives gas $(C)$. Gas $(C)$ on reaction with magnesium gives compound $(D)$ which on hydrolysis again gives gas $(B)$. Identify $(B)$,$(C)$ and $(D)$.

Match List-$I$ with List-$II$

List-$I$ Type of Hydride	List-$II$ Example
$A$. Electron deficient hydride	$I$. $MgH_2$
$B$. Electron rich hydride	$II$. $HF$
$C$. Electron precise hydride	$III$. $B_2H_6$
$D$. Saline hydride	$IV$. $CH_4$

Choose the correct answer from the options given below: