Bond enthalpies H-H, Cl-Cl, and H-Cl bonds are 242 kJ/mol, 242 kJ/mol, and 435 kJ/mol respectively. Enthalpy of formation of HCl is:
a) -146 kJ/mol
b) -333 kJ/mol
c) -193 kJ/mol
d) -435 kJ/mol