Question

2X(g) + Y₂(g) → 2XY(s) The equilibrium constant for the chemical reaction is found to be 2 ×10⁵ at 150 K. If the concentration of X is 4.0 ×10⁻² M, what is the concentration of the Y₂ gas?

A. 3.2 ×10⁻² M
B. 3.1 ×10⁻³ M
C. 1.0 ×10⁻² M
D. 0.5 ×10⁻³ M

Answer 1

The concentration of Y₂ in the equilibrium reaction 2X(g) + Y₂(g) → 2XY(s) is approximately 2.83 × 10⁻² M. Correct option is A.

Step-by-step explanation:

To find the concentration of Y₂ in the equilibrium reaction 2X(g) + Y₂(g) → 2XY(s), we need to use the equilibrium constant (Keq) equation. The equilibrium constant expression for this reaction is Keq = [XY]² / [X]², where [XY] is the concentration of the XY(s) product and [X] is the concentration of X(g).

Given that Keq = 2 × 10⁵ and [X] = 4.0 × 10⁻² M, we can rearrange the equation to find [XY]:

2 × 10⁵ = ([XY]²) / (4.0 × 10⁻²)²

Therefore, [XY]² = (2 × 10⁵) * (4.0 × 10⁻²)²

Taking the square root of both sides, we find [XY] = √((2 × 10⁵) * (4.0 × 10⁻²)²)

Solving this equation, we get [XY] ≈ 2.83 × 10⁻² M, which is closest to option A, 3.2 × 10⁻² M.