Answer
$$K_c = 1.08 \times 10^{7}$$
Work Step by Step
- Calculate all the concentrations:
$$[H_2] = ( 2.50 )/(12.0) = 0.208 M$$
$$[S_2] = ( 1.35 \times 10^{-5} )/(12.0) = 1.13 \times 10^{-6} M$$
$$[H_2S] = ( 8.70 )/(12.0) = 0.725 M$$
1. Write the equilibrium constant expression:
- The exponent of each concentration is equal to its balance coefficient.
$$K_c = \frac{[Products]}{[Reactants]} = \frac{[ H_2S ] ^{ 2 }}{[ H_2 ] ^{ 2 }[ S_2 ]}$$
2. Substitute the values and calculate the constant value:
$$K_c = \frac{( 0.725 )^{ 2 }}{( 0.208 )^{ 2 }( 1.13 \times 10^{-6} )} = 1.08 \times 10^{7}$$
