Question

For the reaction CO(g) + 3 H2(g) ⇌ H2O(g) + CH4(g), Kc = 189 at 1000 K. If a vessel is filled with these gases such that the initial concentrations are [CO] = 0.0360 M, [H2] = 0.0450 M, [H2O] = 0.0200 M, and [CH4] = 0.0310 M, in which direction will a reaction occur and why?

Answer 1

There will be no change since Qc = Kc

Step-by-step explanation:

Given:

[CO] = 0.0360 M

[H2] = 0.0450 M

[H2O] = 0.0200 M

[CH4] = 0.0310 M

Kc = 189

To determine:

The direction in which the given reaction will occur

Calculation:

The given reaction is:

`CO(g) + 3 H2(g) \rightleftharpoons  H2O(g) + CH4(g)`

The relation between the equilibrium constant Kc and the reaction quotient Qc determines the reaction direction

`Qc = ([Products])/([Reactants) \\\\For\ the\ given\ reaction\\\\Qc = ([H2O][CH4])/([CO][H2]^(3) ) -----(1)`

If Qc > Kc reaction will shift to the left

If Qc < Kc reaction will shift to the right

If Qc = Kc there will be no shift

Based on equation (1), for the given reaction:

`Qc= ([0.0200][0.0310])/([0.0360][0.0450]^(3) ) =189`

Since Qc=Kc, there will be no change in the reaction direction and the equilibrium will be retained