Hydrogenation of double and triple bonds is an important industrial process. Calculate (in kJ) the standard enthalpy change ΔH for the hydrogenation of ethyne (acetylene) to ethane:

H−C≡C−H(g)+H2→H3C−CH3(g)
Bond enthalpies (in kJ/mol):

C−C (342)

C≡C (818.4)

C−H (403.4)

H−H (433.7)