Thermochemistry

 34) CH₃OH(g) CO(g) + 2H₂(g)          ΔH = +90.7 kJ

       (a) Heat is absorbed because a positive sign for an enthalpy change, ΔH, represents an endothermic reaction.

       (b) m = 1.60 kg CH₃OH

            ΔH = 1.60 kg CH₃OH x 10³ g/kg x 1 mol CH₃OH/32.05 g CH₃OH x 90.7 kJ/1 mol CH₃OH = 4.53 x 10³ kJ

       (c) ΔH = 64.7 kJ

            m = 64.7 kJ x 1 mol CH₃OH/90.7 kJ x 2 mol H₂/1 mol CH₃OH x 2.02 g H₂/1 mol H₂ = 2.88 g H₂

       (d) ΔH = -90.7 kJ

       (e) m = 32.0 g CO

            ΔH = 32.0 g CO x 1 mol CO/28.01 g CO x -90.7 kJ/1 mol CO = -104 kJ