Atomic hydrogen combines with almost all elements but molecular hydrogen does not. Explain.
Atomic hydrogen is highly unstable. Since, the electronic configuration of atomic hydrogen is 1s1, it needs one more electron to complete its configuration and gain stability. Therefore, it, however, reacts in three different ways i.e.,
(i) by loss of its single electron to form H+.
(ii) by gain of one electron to form H- and
(iii) by sharing its electron with other atoms to form single covalent bonds. In contrast, the bond dissociation energy from H-H bond is very high . As a result, molecular hydrogen is almost inert at room temperature and hence reacts only with a few elements.
