Question

Question 9.7 Discuss the consequences of high enthalpy of H–H bond in terms of chemical reactivity of dihydrogen.

Class XI Hydrogen Page 289

Answer 1

Hydrogen is relatively unreactive at room temperature due to high bond dissociation enthalpy of H--H bond.so, at high temperature or the presence of catalysts , it combines with metal and non- metal to form hydride.

Answer 2

Answer:

The ionization enthalpy of H–H bond is very high (1312 kJ/mol).

This indicates that hydrogen has a low tendency to form H+ ions.

Its ionization enthalpy value is comparable to that of halogens.

Hence, it forms diatomic molecules (H2), hydrides with elements, and a large number of covalent bonds.

Since ionization enthalpy is very high, hydrogen does not possess metallic characteristics (lustre, ductility, etc.) like metals.