Elements hydrogen reacts with other substances only slowly at room temperature. Why?

Explanation

In the elementary state, hydrogen exists in diatomic form i.e. as `H_(2)(g)` and the two hydrogen atoms are linked to each other by single covalent bond (H-H). Since the bond dissociation energy is very high `(435.9kJ mol^(-1))`, therefore, bond cleavage is extremely difficult. As a result, elemtal hydrogen is little reactive at room temperature.