Consider the chemical reaction: N2 3H2 yields 2NH3. If the concentration of the reactant H2 was increased from 1.0 x 10-2 M to 2.5 x 10-1 M, calculate the reaction quotient (Q) and determine which way the chemical system would shift by comparing the value of Q to K.

In this equilibrium, the chemical system will shift to the right in order to produce more NH₃.

The equilibrium constant of a reaction is defined as:

"The ratio between equilibrium concentrations of products powered to their reaction quotient and  equilibrium concentration of reactants powered to thier reaction quotient".

The reaction quotient, Q, has the same algebraic expressions but use the actual concentrations of reactants.

To solve this question we need this additional information:

For this reaction, K = 6.0x10⁻² and the initial concentrations of the reactants are:

[N₂] = 4.0M; [NH₃] = 1.0x10⁻⁴M and [H₂] = 1.0x10⁻²M

Thus, for the reaction:

N₂ + 3H₂ ⇄ 2NH₃

The equilibrium constant, K, of this reaction, is defined as:

Where [] are concentrations in equilibrium.

And Q, is:

Where actual concentrations are:

[NH₃] = 1.0x10⁻⁴M

[N₂] = 4.0M

[H₂] = 2.5x10⁻¹M

Replacing:

Q = 1.6x10⁻⁷

As Q < K,

The chemical system will shift to the right in order to produce more NH₃

Learn more about chemical equililbrium in:

c. electrical charges of ionic bonds.