Question

A) In the presence of excess oxygen, methane gas burns in a constant-pressure system to yield carbon dioxide and water:

CH₄ (g) + 2O₂ (g)  CO₂ (g) + 2H₂O (l) ΔH = -890.0 kJ

Calculate the value of q (kJ) in this exothermic reaction when 1.60 g of methane is combusted at constant pressure.

-0.0112 kJ

34.8 kJ

-89.0 kJ

-8.90 × 104kJ

0.0288 kJ

B) For which of the following reactions is ΔH∘rxn equal to ΔH∘f of the product(s)? You do not need to look up any values to answer this question.

Check all that apply.

View Available Hint(s)

Check all that apply.

Li(s)+12Cl2(l)→LiCl(s)

2Li(s)+Cl2(g)→2LiCl(s)

C(s,graphite)+O2(g)→CO2(g)

BaCO3(s)→BaO(s)+CO2(g)

CO(g)+12O2(g)→CO2(g)

Li(s)+12Cl2(g)→LiCl(s)

C) Which is more stable at room temperature, a F2 molecule or two separate F atoms?

F2 molecule

Two separate F atoms

They are equally stable at room temperature.

There is not enough information given.

D) What is the energy difference between the F2 molecule and the separated atoms?

Express your answer in kilojoules per mole to three significant figures.

Answer 1