Page 1 of 1

Result of Only Adding One of the Reactants

Posted: Sun Jan 13, 2019 3:07 pm
by Joon Chang 2F
Can someone explain what will happen if only one of the reactants is added to a chemical equation?
For example, in the equation 4NH3(g) + 5O2(g) 4NO(g) + 6H2O(g), if only NH3 is added to the equation, will equilibrium shift toward the products?

Re: Result of Only Adding One of the Reactants

Posted: Sun Jan 13, 2019 3:17 pm
by David S
Yes, because by increasing the concentration of any one reactant, the denominator (i.e. the product of reactant concentrations) of the quotient Q will become greater than the denominator of K at equilibrium. Thus, Q < K, and reaction will proceed to balance this larger denominator out by creating more product.

Re: Result of Only Adding One of the Reactants

Posted: Sun Jan 13, 2019 3:18 pm
by Timothy_Yueh_4L
By adding more NH3 to the chemical reaction, you increase the concentration of the that particular chemical on the reactants side which gives an Q constant that is lower than the equilibrium constant, Kc. This will result with the forward reaction being favored as more product will be formed until the original equilibrium constant is attained.

Re: Result of Only Adding One of the Reactants

Posted: Sun Jan 13, 2019 4:30 pm
by Melody P 2B
Then, if you were to remove some reactant would the reaction shift left? Towards the reactants to compensate for the loss?

Re: Result of Only Adding One of the Reactants

Posted: Sun Jan 13, 2019 4:50 pm
by Edward Xie 2E
Then, if you were to remove some reactant would the reaction shift left? Towards the reactants to compensate for the loss?


Yep, since Q > K the reaction will shift towards the reactants.