Question

Write the thermochemical equation for the following reactions that occur at constant pressure:

a.Decomposition of mercuric oxide, HgO, to mercury and oxygen gas, requires 87.1 kJ of heat

b.Combustion of hexane, C₆H₁₂, to carbon dioxide gas and water releases 3923.9 kJ of heat

Answer 1

a. 2HgO = 2Hg + O₂ - 87.1 kJ ∆H = 87.1 kJ

b. C₆H₁₂ + 9O₂ = 6CO₂ + 6H₂O + 3923.9 kJ ∆H = 3923.9 kJ