The rate and Extent of chemical change (2)

Question 1

What is activation energy?

Answer 1

The minimum amount of energy for a reaction to occur

Question 2

Effect of changing concentration on equilibrium

Answer 2

• If the concentration of a reactant is increased, more product will be formed until equilibrium is reached again.
• If the concentration of a product is decreases more reactant will react until equilibrium is reached again

Question 3

Effect of changing pressure on equilibrium

Answer 3

• An increase in pressure causes the equilibrium position to shift towards the side with the smallest number of molecules
• A decrease in pressure causes the equilibrium position to shift towards the side with the larger number of molecules

Question 4

Effect of changing temperature on equilibrium

Answer 4

• If the temperature of an equilibrium system is increased, then the relative amount of products at equilibrium
• Increases for an endothermic reaction
• Decreases for an exothermic reaction

Question 5

What is equilibrium?

Answer 5

When a reversible reaction occurs in an apparatus which prevents the escape of reactants and products
- Equilibrium is reached when the forward and the reverse reactions occur at exactly the same rate

Question 6

What is a reversible reaction?

Answer 6

Reactions in which the product from the reaction can react together to form the original reactant
- The direction of reversible reactions can be changed by changing the conditions

Question 7

Le Chatelier’s Principle

Answer 7

If a reaction at equilibrium is subjected to a change in concentration, temperature or pressure, the position of equilibrium will move to counteract the change

Question 8

What can scientists predict using Le Chatelier’s Principle?

Answer 8

The effects of changing
conditions on the position of an
equilibrium (in a closed system)