Question

Many power plants produce energy by burning carbon-based fuels, which also produces carbon dioxide. Carbon dioxide is a greenhouse gas, so over-production can have negative effects on the environment. Use enthalpy of formation data to calculate the number of moles of CO2(g) produced per megajoule of heat released from the combustion of each fuel under standard conditions (1 atm and 25 °C).

Answer 1

2.54 molMJ-1

Step-by-step explanation:

The formation of CO2 is according to the equation;

C(s) + O2(g) -------> CO2

ΔHreaction = ΔHCO2 - [ΔHO2 + ΔHC]

ΔHO2 and ΔHC = 0 KJ

ΔHCO2 = -393.5 KJ

Hence;

ΔHreaction = -393.5 KJ - 0 KJ

ΔHreaction = -393.5 KJ

1 mol of CO2 yields -393.5 KJ/mol

The negative sign only means that heat was evolved in the process.

nCO2 = 1 mol CO2/393.5 KJ * 1 * 10^3 KJ/1MJ

nCO2 = 2.54 molMJ-1