Yr 12 Equilibria revision and A-Level competence

Which of the following reactions is reversible?

• Combustion

• Neutralisation

• Making ammonia in the Haber process

• Making ethanol by fermentation of sugar

Which of these is NOT true for a system at equilibrium?

• There is a closed system

• The forward and reverse reactions are still occurring

• The rate of the forward reaction is equal to the rate of the reverse reaction

• The concentration of the reactants and products is equal

Which word describes a reaction where all the reactants and products are in the same state?

• Hetereogeneous

• Standard

• Homogeneous

• Non-standard

Which word describes a reaction where the reactants and products are in different states?

• Hetereogeneous

• Standard

• Homogeneous

• Non-standard

Which of these are required for a reaction or system to reach equilibrium? Click all that apply.

• The reaction must be reversible

• The reactants and products must all be gases

• The products must be able to break apart or react to form the reactants

• The system must be closed or sealed

Which factors can affect the position of equilibrium? Click all that apply.

• Using a catalyst

• Temperature

• Pressure

• Concentration

In the following reaction: 3H_2(g) + N_2(g) ↔ 2NH_3(g) when the pressure is increased:

• The position of equilibrium moves to the left

• The position of equilibrium moves to the right

• There is no change in the position of equilibrium

• Equilibrium is achieved more quickly

In the following reaction: 2SO_2(g) + O_2(g) ↔ 2SO_3(g) when the pressure is decreased:

• There is no change in the position of equilibrium

• Equilibrium is achieved more quickly

• The position of equilibrium moves to the left

• The position of equilibrium moves to the right

In the following reaction: 3H_2(g) + N_2(g) ↔ 2NH_3(g) the forward reaction is exothermic. When the temperature is increased: Click all the correct statements:

• The position of equilibrium moves to the left

• The position of equilibrium moves to the right

• More NH₃ is produced

• Less NH₃ is produced

Consider the following reaction: 2SO_2(g) + O_2(g) ↔ 2SO_3(g) in which the forward reaction is exothermic. Which statement is true?

• Pressure will not affect the position of equilibrium

• Increasing the concentration of oxygen will decrease the amount of SO₃ produced

• Increasing the concentration of SO₂ will decrease the amount of SO₃ produced

• Decreasing the temperature moves the position of equilibrium to the right