Propane (C3H8) is a component of natural gas and is used in domestic cooking and heating. It burns according to the following reaction:

C3H8 + O2 → CO2 + H2O

a. Balance the equation representing the combustion of propane in air.
b. How many grams of carbon dioxide can be produced by burning 20.0 pounds of propane, the typical size of a BBG grill propane tank?
Assume that oxygen is the excess reagent in this reaction.