Question

At 1990 K and 1 atm pressure, there are equal numbers of Cl₂ molecules and Cl atoms in the reaction mixture. The value of K_p for the reaction Cl₂(g) ⇌ 2Cl(g) under the above conditions is x × 10⁻¹. The value of x is ______. (Rounded-off to the nearest integer)

Options

• 1

• 3

• 5

• 7

Answer 1

At 1990 K and 1 atm pressure, there are equal numbers of Cl₂ molecules and Cl atoms in the reaction mixture. The value of K_p for the reaction Cl₂(g) ⇌ 2Cl(g) under the above conditions is x × 10⁻¹. The value of x is 5.

Explanation:

Cl₂ ⇌ 2Cl

Moles of Cl₂ = moles of Cl = x .....(given)

∴ Total no. of moles = x + x = 2x

\[\ce{P_{Cl_2}}\] = `"x"/(2"x") xx 1 = 1/2`

P_Cl = `"x"/"2x" xx 1 = 1/2`

∴ K_p = `("P"_"Cl")^2/"P"_"Cl"`

= `((1/2)^2)/(1/2)`

= `1/2`

= 0.5

= 5 × 10⁻¹

Hence value of x = 5