1. Which of the following is a correctly written thermochemical equation?
 NH4Cl NH4+ + Cl
 2C8H18 + 25O2 16CO2 + 18H2O, H = 5,471 kJ/mol
 Fe (s) + O2 (g) Fe2O3 (s), H = 3,926 kJ
 -->C3H8 (g) + 5O2 (g) 3CO2 (g) + 4H2O (l), H = 2,220 kJ/mol
 2. How does a phase change affect a thermochemical equation?
 It alters the moles of reactants.
 -->It can affect the (delta) H value.
 It alters the products.
 It affects the balance of the equation.