Which element accepts one electron to achieve a noble gas-like configuration?

Hydrogen readily combines with metals and thus shows its

The number of hydrogen molecules possible from its isotopes is

At $298.2 \ K$,the relationship between the enthalpy of bond dissociation (in $kJ \ mol^{-1}$) for hydrogen $(E_{H})$ and its isotope,deuterium $(E_{D})$,is best described by:

Select the correct statement regarding interstitial hydrides.

Why does hydrogen occur in a diatomic form rather than in a monoatomic form under normal conditions?