GCSE AQA Equilibrium & Haber Process

dynamic equilibrium

rate of the forward reaction = rate of the back reaction

LeChatelier's Principle

whatever is changed in a reversible reaction, it will shift in the direction to oppose that change

Reversible Reaction

Reactants change to products, but the products can also change back to the reactants

Adding Products

shift to left making more Reactants

Removing Products

shift to right making more Products

An increase of pressure

Only effects Gases! Causes a shift to the side with the fewer moles of gas

A decrease in pressure

Only effects Gases! Causes a shift to the side with more moles of gas

Catalyst

Does not alter the Equilibrium! Only speeds up the time it takes to achieve the equilibrium

+ΔH Positve Enthalpy Value

Endothermic reaction

-ΔH Negative Enthalpy Value

Exothermic reaction

Adding reactants

shift to the right

Removing reactants

shift to the left

Solute

substance being dissolved

Solution

combination of solute and solvent

Rate of Reaction

Not to be confused with Equilibrium, the determines the speed of a reaction. How quickly the Equilibrium is achieved

What is made in the Haber process?

Ammonia (NH3)

What are the uses of ammonia?

Fertilisers, making nitric acid

What is the equation for the Haber Process?

Where are the raw materials in the Haber Process obtained from?

Nitrogen from the air, hydrogen from natural gas

Why is the ammonia removed from the process as it forms?

Because the process is reversible, so removing ammonia reduces the backward reaction

How do we make sure the reactants are not wasted?

Unused nitrogen and hydrogen are recycled.

Is the Haber Process and exothermic or and endothermic process?

Exothermic

What are the compromise conditions required for the Haber Process?

200atm

450 degrees celcius

Iron catalyst

Why is the temperature a compromise condition?

Low temperature required as process is exothermic, but low temperature would make the reaction occur very slowly

Why is the pressure a compromise condition?

To produce the most ammonia a high pressure is required but a high pressure is dangerous and expensive