Question

I really need some help and explaining with the Heat of Combustion Lab.

1. You may recall that the products of the complete combustion of a hydrocarbon are water vapor and carbon dioxide gas. Write the balanced equation showing the combustion of methane. Do not forget to include the states of matter of the reactants and the products. Hint: Methane is a gas at standard temperature and pressure.

Answer 1

To begin the experiment, a bomb calorimeter is filled with 1.11g CH4 and an excess
of oxygen. The heat capacity of the calorimeter, including the bomb and the water, is 4.319 kJ g ⋅ °C . The initial temperature of the system was 24.85°C, and the final temperature was 35.65°C.
2. Calculate the change in temperature, ∆Τ.

Answer 2

3. Using the formula ∆H = −m ⋅C ⋅ ∆T , calculate the heat of combustion of 1.11g CH4 .
4. Evaluate the information contained in this calculation and complete the following sentence:This calculation shows that burning ________ grams of methane [takes in/gives off] __________ energy.

Answer 3

5. The molecular mass of methane is 16.4 g. Calculate the number of moles of methane burned in the experiment.
6. What is the experimental molar heat of combustion?
7. The accepted value for the heat of combustion of methane is 890 kJ/mol. Explain why the experimental data might differ from the theoretical value.

Answer 4

8. Given the formula % error = theoretical value − experimental value ⋅100 , calculate theoretical value
the percent error for the experiment.

Answer 5

@aaronq