Rates of reaction

Question 1

what affects the rate of reaction

Answer 1

• temperature
• surface are of solid
• concentration of solid
• pressure of gas
• catalysts

Question 2

definition of activation energy

Answer 2

the minimum amount of energy that particles need to react

Question 3

how do reactions occur

Answer 3

-collision theory: particles must collide to react
- the particles must collide in correct orientation and enough energy (activation energy) to react.
- not all collisions succeeds

Question 4

how does increasing temperature affect rate of reaction

Answer 4

• increases the rate of reaction
• particles gain kinetic energy causing them to move faster so there’s more collisions per unit time
• particles gain more energy so there would be more successful collisions

Question 5

how does increasing surface area affect rate of reaction

Answer 5

• increases the rate of reaction
• particles have more area to collide so there’s more collisions per unit time

Question 6

how does increasing concentration affect the rate of reaction

Answer 6

• increases the rate of reaction
• increases number of reactants in the same volume, more collisions per unit time

Question 7

how does increasing concentration affect the rate of reaction

Answer 7

• increases the rate of reaction
• particles are more crowded therefore, more collisions per unit time

Question 8

how does a catalyst affect the rate of reaction

Answer 8

• increases the rate of reaction
• provide an alternative reaction pathway with a lower activation energy meaning there would be more successful collisons

Question 9

equation for reaction rate

Answer 9

amount of product formed or amount of reactant used / time

Question 10

definition of exothermic reactions

Answer 10

releases energy into the surroundings and the temperature of the surrounding increases

Question 11

definition of endothermic reactions

Answer 11

absorbs energy from the surroundings and the temperature of the surrounding decreases