14.4 What Does The Equilibrium Constant Tell Us

Question 1

Define the reaction quotient. How does it differ from equilibrium constant?

Answer 1

If a reaction has not reached equilibrium and we substituted the initial M into the equilibrium constant expression, then we obtain reaction quotient

It can be obtained at any M whereas equilibrium constant is obtained at M’s corresponding to equilibrium state

Question 2

O outline the steps for calculating the M’s of reacting species in an equilibrium reaction

Answer 2

1. Write chemical equations for the equilibrium
2. Write equilibrium constant expression for the reaction
3. Express all unknown M’s in terms of a single variable x
4. Substitute the equilibrium M’s in terms of x in the equilibrium constants expression
5. Solve the equation of x
6. Substitute the value obtained for x in the expressions in step to calculate equilibrium M’s or equilibrium partial pressures