C8 (Rates And Equilibrium)

Question 1

Explain the line on a (time-amount of product formed) graph

Answer 1

• steeper the line the faster the rate of reaction

- it evens out when products are used up

Question 2

2 factors of Collision Theory

Answer 2

• collision frequency of reacting products is how often they collide and the more collisions the faster the reaction
• particles have to collide with enough energy for the collisions to be successful

Question 3

4 factors rate of reaction depends on

Answer 3

• temperature as it makes particles move quicker, collide more, more energy
• concentration as more particles in same volume
• surface area when breaks up into smaller pieces more chances of collisions
• catalyst speeds up reaction without getting used up, can lower activation energy

Question 4

Rate of reaction =

Answer 4

Amount of reactant used up of product formed / time

Question 5

3 ways to measure rates of reaction

Answer 5

• precipitation becomes cloudy and colour change
• change in mass, quicker reading on balance drops faster rate
• volume of gas given off with a syringe

Question 6

Reversible Reactions

Answer 6

• The reactants can react to form the products and can react the other way
• rate is equal
• dynamic equilibrium as the concentrations don’t change

Question 7

If equilibrium lies to the right

Answer 7

Concentration of products greater then reactants

Question 8

If equilibrium shifts to left

Answer 8

Concentration of reactants greater than products

Question 9

3 factors position of equilibrium depends on

Answer 9

• temperature more to right (Ammonia)
• pressure in gases
• concentrations of reactants and products

Question 10

Reversible reactions energy transfer

Answer 10

• if endothermic one way, exothermic the other way

- energy transferee to and from system is always equal

Question 11

La Chatelier’s Principle

Answer 11

If you change conditions in a reversible reaction at the equilibrium, the system will try to counteract the change

Question 12

3 factors in Le Chatelier’s Principle

Answer 12

• temperature decrease exothermic direction with more products, increase endothermic direction with more products
• increased pressure tries to decrease it by moving less molecules, decrease pressure tries to increase by moving more molecules with balanced symbol reaction with more molecules of gas with more moles
• concentration change there will be no equilibrium, so it tries to bring it back