Question

3. Calculate the equilibrium constant ( Ke ) for the reaction below if the equilibrium mixture for the reaction was found o contain [ H₂S ] 0.25 M. [ H₂ ] = 1 M , and [ S₂ ] -0.2 M. 2H₂S ( g ) 2H₂ ( g ) + S2 ( g )

Answer 1

The equilibrium constant relates the concentrations of the products and reactants in the chemical equilibrium. To calculate it we can apply the following equation.

For the reaction: aA + bB ---> cC + dD

Equlibrium constant (Ke) will be:

`K=(\lbrack C\rbrack^c*\lbrack D\rbrack^d)/(\lbrack A\rbrack^a*\lbrack B\rbrack^b)`

The letters in square brackets refer to the concentration raised to the respective coefficient. Now we replace the known values:

`\begin{gathered} K=\text{ }(\lbrack H_2\rbrack^2*\lbrack S_2\rbrack^1)/(\lbrack H_2S\rbrack^2) \\ K=(\lbrack1M\rbrack^2*\lbrack0.2M\rbrack^1)/(\lbrack0.25M\rbrack^2) \\ K=(1M^2*0.2M)/(0.0625M^2) \\ K=3.2M \end{gathered}`

So, the equilibrium constant (Ke) will be 3.2M