Atomic hydrogen combines with almost all elements but molecular hydrogen does not. Explain.

Explanation

Atomic hydrogen is highly unstable and hence it is very reactive. Its electronic configuration is `1s^1`. For stability it accept 1 more electron and thus it almost combine with all the elements.
Atomic hydrogen make hydride by three different type.
(i) If remove one electron and form `H^+`
(ii) It accept one electron and form `H^-`
(iii) It share one electron and form covalent single bond. In contrast, the bond dissocia tion energy of H-H bond is very high (435.88 kJ `"mol"^(-1)`). As a result molecular hy drogen is almost inert at room temp. and hence reacts only with a few elements.