Question

The concentrations of reactants and products for a chemical reaction can be calculated if the equilibrium constant for the reaction and the starting concentrations of reactants and/or products are known.

Consider the reaction

CO(g)+NH3(g)⇌HCONH2(g),    Kc=0.890

If a reaction vessel initially contains only CO and NH3 at concentrations of 1.00 M and 2.00 M, respectively, what will the concentration of HCONH2 be at equilibrium?

Please show all steps! Thank you!

Answer 1

                              CO(g)   +    NH3(g)    ⇌ HCONH2(g),    Kc =0.890    

Initial                       1 M             2 M                      0

at equilibruim         1-x             2 -x                        x

             Kc = equilibrium concentration of products/ equilibrium concentration of reactants

          0.89 = x / (1-x) (2-x)

     0.89 ( x² - 3x +2 ) = x

     0.89 x² - 2.67 x + 1.78 = x

     0.89 x² - 3.67 x + 1.78 = 0

On solving,

x = 0.56 M

Therefore,

concentration of HCONH2 at equilibrium = 0.56 M