Question

The following reaction was carried out in a 3.25 L reaction vessel at 1100 K: C(s)+H2O(g)⇌CO(g)+H2(g) If during the course of the reaction, the vessel is found to contain 8.75 mol of C, 12.9 mol of H2O, 3.70 mol of CO, and 8.50 mol of H2, what is the reaction quotient Q?

Answer 1

C(s)+H2O(g)⇌CO(g)+H2(g)

Reaction quotient, Q = [CO][H2]/[H2O] only gas molecules were included because C(s) for any solid concentration become 1 (constant)

[H2] = concentration of H2 molecule square bracket means concentration in chemistry

[CO] = 3.7 / 3.25 = 1.138 M (to calculate the concentration divide the given concentration with volume of vessel)

Calculate for other remaining gaseous molecules using the same formula

[H2] = 8.50 / 3,25 = 2.615 M

[H2O] = 12.9 / 3.25 = 3.969 M

now apply these values in the reaction quotient expression
Q = [CO] [H2] / [H2O] = 1.138 x 2.615 / 3.969 = 0.75