A gaseous fuel mixture contains 20.9% methane (CH4), 43.2% ethane (C2H6) and the rest propane (C3H8) by volume.

Question

Part A
When the fuel mixture contained in a 1.58 L tank, stored at 748 mmHg and 298 K, undergoes complete combustion, how much heat is emitted? (Assume that the water produced by the combustion is in the gaseous state.)
Express your answer with the appropriate units.

Answer 1

1. Start with 1.58 L sample. Use PV = nRT at the conditions listed and calculate n = total mols.
2. n*% each gas = mols of each gas.
3. Write equation for combustion of each gas.
4. Look up heat combustion per mole for each gas and calculate heat generated by each gas based on the moles of that gas.
5. Add heat generated by each gas for total heat generated.
Post your work if you get stuck.