Question

A sealed isothermal container initially contained 2 moles of CO gas and 3 moles of H2 gas. The following reversible reaction occured: CO(g) + 2H2(g) ---> CH3OH(g). At equilibrium, there was 1 mole of CH3OH in the container. What was the total number of moles of gas present in the container at equilibrium.

A.) 1
B.) 2
C.) 3
D.) 4

Answer 1

(c) Total Number of moles = 3

Step-by-step explanation:

To solve this question we have to follow the stoichiometry of the reaction and the fact that at equilibrium we have 1 mol of CH₃OH using the mnemonic helper RICE ( Reaction, Initial, Change, Equilibrium) as follows:

R CO(g) + 2 H₂ (g) ⇄ CH₃OH (g)

I (mol) 2 3 0

C (mol) -x x -2x + x

E (mol) 2-x 3-2x x

But we are told that at equilibrium x = mol CH₃OH = 1 , then at equilibrium we will have

E (mol) 2-(1) 3-2(1) 1

E (mol) 1 1 1

Therefore, the total number of moles of gas present in the container at equilibrium was 3