Answer
$$K = 1.7 \times 10^{-5}$$
Work Step by Step
- Calculate all the concentrations:
$$[NOCl] = ( 1.0 )/(3.0) = 0.33 M$$
$$[NO] = ( 4.5 \times 10^{-3} )/(3.0) = 1.5 \times 10^{-3} M$$
$$[Cl_2] = ( 2.4 )/(3.0) = 0.80 M$$
- The exponent of each concentration is equal to its balance coefficient.
$$K = \frac{[Products]}{[Reactants]} = \frac{[ NO ] ^{ 2 }[ Cl_2 ]}{[ NOCl ] ^{ 2 }}$$
2. Substitute the values and calculate the constant value:
$$K = \frac{( 1.5 \times 10^{-3} )^{ 2 }( 0.80 )}{( 0.33 )^{ 2 }} = 1.7 \times 10^{-5}$$
