Given Ag 3Bg Cg 2Dg The answer key says the correct answer

Given: A(g) +3B(g) <--> C(g) + 2D(g)

The answer key says the correct answer is 27. I don\'t know how to calculate it since [C] is not given. Please explain your answer.

Solution

set up an ICE chart, you need the volume to determine molarity for the ICE chart
1mole / 5L = 0.2M

...[A]....3[B].....[C]...2[D]
...0.2....0.2.......0.......0
...-x......-3x.....+x....+2x
.0.2-x...0.2-3x...x......2x

2x = 0.5moles / 5L = 0.1M
so, x = 0.05M

[A] = 0.2 - 0.05 = 0.15M
[B] = 0.2 - 0.15 = 0.05M
[C] = 0.05M
[D] = 0.1M

Kc = (0.05)(0.1)^2 / (0.15)(0.05)^3
Kc = 0.0005 / 0.0000188
Kc = 26.67