Hydrogen can be obtained from water,by the action of water on

Atoms in hydrogen gas have a preponderance of which isotope?

$2BeCl_2 + LiAlH_4 \rightarrow X + LiCl + AlCl_3$

How can the production of hydrogen from water gas be increased by using the water gas shift reaction?

Formic acid is heated with conc. $H_2SO_4$ at $100^{\circ}C$ to form $A$ and $B$. When $Fe_2O_3$ is heated strongly with $B$,the products formed are $C$ and $D$. $C$ can also be obtained by reacting $CaCO_3$ with dil. $HCl$. What is $D$?

Deuterium differs from hydrogen in