Le Chatelier's Principle Chemistry Example 2

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Example 2

medium
For the exothermic reaction N2+3H2⇌2NH3+heat\text{N}_2 + 3\text{H}_2 \rightleftharpoons 2\text{NH}_3 + \text{heat}, predict the effect of: (a) increasing temperature, (b) removing NH3\text{NH}_3, (c) increasing pressure.

Solution

  1. 1
    (a) Increasing temperature adds heat. Since heat is a 'product' (exothermic), the system shifts left (toward reactants) to consume the excess heat. This decreases NH3\text{NH}_3 yield.
  2. 2
    (b) Removing NH3\text{NH}_3 reduces a product. The system shifts right (toward products) to replace the removed NH3\text{NH}_3.
  3. 3
    (c) Increasing pressure favors the side with fewer gas moles. Reactants have 1+3=41 + 3 = 4 moles of gas; products have 2 moles. The system shifts right, producing more NH3\text{NH}_3.

Answer

(a) shift left, (b) shift right, (c) shift right\text{(a) shift left, (b) shift right, (c) shift right}
Industrial ammonia production (Haber process) uses high pressure and moderate temperature as a compromise — high pressure favors product, but low temperature (while favoring product) makes the reaction too slow. A catalyst is used to speed up the reaction at moderate temperatures.

About Le Chatelier's Principle

When a system at chemical equilibrium is subjected to an external stress — such as a change in concentration, pressure, or temperature — the equilibrium.

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More Le Chatelier's Principle Examples

Example 1 easy

State Le Chatelier's principle and explain what it predicts about equilibrium systems.

Example 3 medium

For the equilibrium [formula] (endothermic), predict the effect of increasing temperature on the amo

Example 4 hard

The contact process produces sulfur trioxide: [formula], [formula]. Explain why the industrial proce

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