Question

When 6.35 g of hydrogen iodide (HI) is placed in a closed, 2 L, container, at 35°C, it will decompose into its elements hydrogen and iodine and an equilibrium will be established:

2 HI (g) ⇌ H₂(g) + I₂(g) Kc=2.2x10⁻³

Write the expression for Kc.

a. [H₂][I₂]/[HI]²
b. [HI]²/[H₂][I₂]
c. [H₂][I₂]/Kc
d. [HI]²/Kc

Answer 1

The expression for Kc is [H₂][I₂]/[HI]².

Step-by-step explanation:

The expression for Kc for the reaction 2 HI (g) ⇌ H₂(g) + I₂(g) is:

a. [H₂][I₂]/[HI]²

Here, the concentration of H₂ and I₂ are multiplied together and divided by the square of the concentration of HI. This expression represents the equilibrium constant Kc for the given reaction.