Rates And Equillibria

Question 1

What is collision theory?

Answer 1

Collision theory states that chemical reactions only occur when particles collide with each other and sufficient energy- reach activation energy

Question 2

Which factors affect the rate of reaction?

Answer 2

• Concentration of solutions
• Temperature
• Presence of catalysts
• Surface area
• Pressure of gases

These factors influence the frequency and effectiveness of collisions between reacting particles.

Question 3

How does increasing concentration affect the rate of reaction?

Answer 3

increases the rate of reaction because there will be more frequent successful collisions, due to more particles present in a given volume

Question 4

How does increasing temperature affect the rate of reaction?

Answer 4

increases the rate of reaction because particles gain kinetic energy so they move faster with more energy, leading to more collisions and a higher likelihood of achieving activation energy

Question 5

How does adding a catalyst affect the rate of reaction?

Answer 5

Increases the rate of reaction by lowering the activation energy needed for the reaction, providing an alternative route for the reaction, increasing the number of effective collisions

Question 6

How does increasing surface area affect the rate of reaction?

Answer 6

increases the rate of reaction because more of the surface is exposed and collide, leading to more effective collisions

Question 7

How does increasing pressure affect the rate of reaction?

Answer 7

increases the rate of reaction because the volume is reduced and concentration increases, meaning particles are more compact together, resulting in more successful collisions.

Question 8

If the temperature is increased at equilibrium, the products will:

Answer 8

Products will increase for endothermic reaction
Products will decrease for exothermic reaction

Question 9

If the temperature is decreased at equilibrium, the products will:

Answer 9

Products will decrease for endothermic reaction
Products will increase for exothermic reaction

Question 10

What do the amount of products and reactants depend on

Answer 10

The conditions of the reaction (e.g. concentration, temperature, pressure

Question 11

What is Le Chateliers principle?

Answer 11

If there is a change in the conditions of a system, the equilibrium will shift to counteract the change

Question 12

3 factors that affect the position of equilibria

Answer 12

Concentration, temperature, pressure in gases

Question 13

How does increasing temp affect position of equilibria?

Answer 13

Increasing, makes reaction go in the endothermic direction
Decreasing, makes reaction go in the exothermic

Question 14

How does increasing pressure affect position of equilibria?

Answer 14

Only had effect if: gaseous state, different number of molecules on each side
Increasing, shifts to side with fewer moles of gas
Decreases, shifts to side with more moles of gas

Question 15

How does increasing concentration affect position of equilibria?

Answer 15

Increasing, shifts away from substance you have added
Decreasing, shifts towards substance you have added

Question 16

How does adding a catalyst affect position of equilibria?

Answer 16

No effect on position because it speeds up both forward and backward reaction by same amount

Question 17

What is a catalyst and how does it work?

Answer 17

Catalysts are biological enzymes which increase the rate of reaction by providing a different pathway (lowering activation the energy) without being used up

Question 18

What is activation energy

Answer 18

The minimum amount of energy that particles must have to react