Chapter 5, Problem 68
Dimethyl ether, CH3OCH3(π), is an industrially useful organic compound that is a gas at room temperature. Consider the following balanced thermochemical equations:
CH3OCH3(g) + 3 O2(g) β 2 CO2(g) + 3 H2O(g) ΞHΒ° = β1328 kJ
CH4(g) + 2 O2(g) β CO2(g) + 2 H2O(g) ΞHΒ° = β802 kJ
2 C2H6(g) + 7 O2(g) β 4 CO2(g) + 6 H2O(g) ΞHΒ° = β2855 kJ
a. All three of the above reactions produce H2O(π). If they were written to produce H2O(π) instead, would the values of Ξπ»Β° become more negative, become less negative, or stay the same?
b. By using Hessβs law and the reactions provided, calculate Ξπ»Β° for the following balanced reaction between dimethyl ether and methane to produce ethane and water:
CH3OCH3(g) + 2 CH4(g) β 2 C2H6(g) + H2O(g)