Natural gas is very abundant in many Middle Eastern oil fields. However, the costs of shipping the gas to markets in other parts of the world are high because it is necessary to liquefy the gas, which is mainly methane and has a boiling point at atmospheric pressure of -164oC. One possible strategy is to oxidize the methane to methanol, CH3OH, which has a boiling point of 65oC and can therefore be shipped more readily. Suppose that 10.7 x 109 ft3 of methane at atmospheric pressure and 25oC is oxidized to methanol.
(a) What volume of methanol is formed if the density of CH3OH is 0.791 g / mL?
(b) Write balanced chemical equations for the oxidations of methane and methanol to CO2 (g) and H2O (l). Calculate the total enthalpy change for complete combustion of the 10.7 x 109 ft3 of methane just described and for complete combustion of the equivalent amount of methanol, as calculated in part (a).
(c) Methane, when liquefied, has a density of 0.466 g / mL; the density of methanol at 25oC is 0.791 g/mL. Compare the enthalpy change upon combustion of a unit volume of liquid methane and liquid methanol. From the standpoint of energy production, which substance has the higher enthalpy of combustion per unit volume?