Unit 7

Question 1

rate of reaction

Answer 1

amount of reactant used or product formed / time

Question 2

measuring rates of reaction

Answer 2

• precipitation
• change in mass
• volume of gas

Question 3

precipitation

Answer 3

• mix 2 reactant solutions in a flask
• put the flask on a piece of paper with a mark on it
• time how long it takes for the mark to disappear

Question 4

change in mass

Answer 4

as gas is released the lost mass is measured on the balance, the quicker the reading drops the faster the reaction

Question 5

volume of gas

Answer 5

• a gas syringe measures the volume of gas given off

- the more gas given off, the faster the reaction

Question 6

factors affecting reaction rate

Answer 6

• concentration/pressure
• surface area
• temperature

Question 7

catalysts

Answer 7

lower the activation energy so theres more successful collisions as they exceed the energy needed

Question 8

exothermic reaction profile

Answer 8

• products are at a lower energy than reactants

- height difference shows energy released

Question 9

endothermic reaction profile

Answer 9

• products are at a higher energy than reactants

- height difference shows energy taken in

Question 10

activation energy

Answer 10

difference between the reactants and the highest point on the curve

Question 11

overall energy change

Answer 11

energy to break bonds - energy released forming bonds

Question 12

breaking bonds

Answer 12

• energy is used

- endothermic

Question 13

forming bonds

Answer 13

• energy is released

- exothermic