Adding reactant to a system at equilibrium makes the quotient smaller than K, so the equilibrium:

1. Adding reactant increases the denominator of the reaction quotient. 2. If reactant is added, or product is removed, then the quotient becomes less than the constant. 3. In that case the equilibrium will shift right. 4. Note the constant itself does not change, only the composition does. _Source: OpenStax Chemistry 2e (CC BY 4.0), Ch 13 'Fundamental Equilibrium Concepts', sections 13.1-13.4_