Answer:
[Y₂] = 31.25M
Step-by-step explanation:
Based on the chemical reaction:
2X(g) + Y2(g) ⇌ 2XY(s)
We must define the equilibrium constant, K as:
K = 20 = 1 / [X]²[Y₂]
Where [X] and [Y₂] are the equilibrium concentrations of each gas.
If [X] = 4.0x10⁻²M:
20 = 1 / [4.0x10⁻²M]²[Y₂]
0.032 = 1 / [Y₂]
[Y₂] = 31.25M