What is the energy change that will occur when 25.5 grams of oxygen gas (O2) react with excess methane (CH4) according to the reaction below?

CH4 + 2 O2yields CO2 + 2 H2O delta H = - 889 kJ/mol

Select one:

a. 354 kJ of energy will be given off by the reaction

b. 354 kJ of energy will be absorbed by the reaction

c. 708 kJ of energy will be given off by the reaction

d. 708 kJ of energy will be absorbed by the reaction

Question

Chemistry

Jayden Lawrence

31 May, 21:03

What is the energy change that will occur when 25.5 grams of oxygen gas (O2) react with excess methane (CH4) according to the reaction below?

CH4 + 2 O2yields CO2 + 2 H2O delta H = - 889 kJ/mol

Select one:

a. 354 kJ of energy will be given off by the reaction

b. 354 kJ of energy will be absorbed by the reaction

c. 708 kJ of energy will be given off by the reaction

d. 708 kJ of energy will be absorbed by the reaction

+1

Answers (1)

Know the Answer?

Wagner · Answer 1

Amount of CH4 is excess, so no need to worry about it

but the limiting factor is the Oxygen

according to stranded equation,

CH4 + 2 O2 - - > CO2 + 2 H2O ΔH = - 889 kJ/mol

just by taking proportions

(-889 kJ/mol) / 2 x 0.8 mol = - 355.6 kJ

so i think the answer is (a)