已知\(\rm{C(s)+H_{2}O(g)=CO(g)+H_{2}(g)}\)     \(\rm{ΔH=akJ·mol^{-1\;\;\;\;\;\;}}\)\(\rm{2C(s)+O}\)\(\rm{{\,\!}_{2}}\)\(\rm{(g)=}\)\(\rm{2CO(g)}\)           \(\rm{ΔH=-220 kJ·mol}\)\(\rm{{\,\!}^{-1\;\;\;\;\;}}\)\(\rm{H—H}\)、\(\rm{O=O}\)和\(\rm{O—H}\)键的键能分别为\(\rm{436 kJ·mol}\)\(\rm{{\,\!}^{-1}}\)、\(\rm{496 kJ·mol}\)\(\rm{{\,\!}^{-1}}\)和\(\rm{462 kJ·mol}\)\(\rm{{\,\!}^{-1}}\)，则\(\rm{a}\)为\(\rm{(}\)   \(\rm{)}\)