Which of the following is radioactive?

Identify the electron-rich hydrides from the following.

In the reaction $2X + B_2H_6 \rightarrow [BH_2(X)_2]^+ [BH_4]^-$,the amine$(s)$ $X$ is(are):

Consider the following statements:
$1.$ Atomic hydrogen is obtained by passing hydrogen through an electric arc.
$2.$ Hydrogen gas will not reduce heated aluminium oxide.
$3.$ Finely divided palladium adsorbs large volume of hydrogen gas.
$4.$ Pure nascent hydrogen is best obtained by reacting $Na$ with $C_2H_5OH$.
Which of the above statements is/are correct?

What do you understand by the terms: $(i)$ hydrogen economy,$(ii)$ hydrogenation,$(iii)$ syngas,$(iv)$ water-gas shift reaction,and $(v)$ fuel-cell?

Which of the following statements is not true for hydrogen:
$1)$ It exists as a diatomic molecule.
$2)$ It has one electron in the outermost shell.
$3)$ It can lose an electron to form a cation which can freely exist.
$4)$ It cannot form ionic compounds.