Answer :
Answer:
Part a)
- [NO] = 0.048 mol/L
Part b)
- [Cl₂] = 0.024 mol/L
Explanation:
The complete question is:
At 473 K, for the elementary reaction 2NOCl(g) ⇌2NO(g)+Cl₂(g)
k₁ = 7.8×10⁻² L/mol.s and k⁻¹ =4.7×10²L²/mol².s .
A sample of NOCl is placed in a container and heated to 473 K. When the system comes to equilibrium, [NOCl] is found to be 0.58 mol/L.
Part a) Calculate the concentration of NO
Part b) Calculate the concentration of Cl₂
Solution
1. Calculate the equilibrium constant.
k₁ is the rate constant of the forward reaction and k⁻¹ is the rate constant of the reverse reaction.
The equilibrium constant is the quotient of the rate constant for the forward reaction and the rate constant of the reverse reaction:
[tex]K_{eq}=\dfrac{K}{k^{-1}}=\dfrac{7.8\times 10^{-2}L/mol.s}{4.7\times 10^2L^2/mol^2.s}\\\\\\ K_{eq}=1.6596\times 10^{-4}mol/L[/tex]
2. Build the ICE (Initial, Change, Equilibrium) table
2NOCl(g) ⇌ 2NO(g) + Cl₂(g)
Initial A 0 0
Change -2x +2x +x
Equilibrium A - 2x 2x x
A - 2x = 0.58 mol/L
3. Write the equilibrium constant equation
[tex]K_{eq}=\dfrac{{[NO]}^2].[Cl_2]}{[NOCl]^2}\\ \\ \\ 1.6593\times 10^{-4}mol/L=\dfrac{(2x)^2(x)}{(0.58mol/L)^2}[/tex]
4. Solve the equation
[tex]4x^3=5.5828\times 10^{-5}\\\\\\x=0.0241mol/L[/tex]
5. Concentrations
Part a)
- [NO] = 2x = 2(0.0241mol/L) = 0.048 mol/L
Part b)
- [Cl₂] = x = 0.024 mol/L