Answer to Question #63277 in General Chemistry for S

Question

Chapter 5 (5.119)

World energy supplies are often measured in the unit of quadrillion British thermal units (1012 Btu), generally called a "quad." In 2015, world energy consumption is projected to be 5.81 ×1017kJ.

1) Current annual energy consumption in the United States is 99.6 quads. Assume that all this energy is to be generated by burning CH4(g) in the form of natural gas. If the combustion of the CH4(g) were complete and 100 % efficient, how many moles of CH4(g) would need to be combusted in order to provide the U.S. energy demand?

Answer 1

The heat of combustion for methane as 890 kJ/mole.
If 1 Btu = 1054 J, then the heat of combustion for methane would be 844 Btu/mole.
x mol = 99.6 quadrillion Btu / 844 Btu/mole = 118 trillion moles of CH4