C5 rate of reaction

Question 1

activation energy

Answer 1

The minimum amount of energy needed for a reaction to start

Question 2

what is a catalyst

Answer 2

A substance that increases the rate of reaction, without being used up, by lowering the activation energy needed which leads to more frequent successful collisions

Question 3

concentration

Answer 3

A measure of the amount of dissolved solute present in a solution

Question 4

rate of reaction

Answer 4

The measure of the change in concentration of the reactants or products per unit of time

Question 5

successful collisions

Answer 5

A collision between two particles with enough energy for a reaction to happen

Question 6

what is an enzyme

Answer 6

a protein which is a biological catalyst which speeds up reactions without being used up themselves

Question 7

what is a reactant

Answer 7

A substance that takes part in a chemical reaction

Question 8

what is a product

Answer 8

The substance(s) formed in a chemical reaction

Question 9

factors that effect of the rate of reactions

Answer 9

1. increased temperature
2. increased concentration
3. increased surface area

Question 10

The rate of a reaction depends on two things:

Answer 10

• the energy with which particles collide.
• the frequency of collisions between particles

Question 11

How does temperature affect the rate of particle collision?

Answer 11

• particles have more energy
• they move faster
• There are more frequent successful collisions
• More particles have the activation energy

Question 12

The higher the concentration of a dissolved reactant?

Answer 12

• the faster the rate of a reaction
• there are more particles in the same amount of space or the particles become more crowded
• particles have more frequent successful collisions

Question 13

Effect of pressure on rate of reaction

Answer 13

• the faster the rate of a reaction
• the space in which the gas particles are moving becomes smaller
• the gas particles become closer together, or they become more crowded
• More frequent successful collisions

Question 14

Effect of surface area on rate of reaction

Answer 14

• If the solid is split into several pieces: e.g. a powder
• the surface area increases
• more reactant particles are available on the surface
• More frequent successful collisions

Question 15

why is a catalyst useful

Answer 15

• Catalysts lower the reaction’s activation energy (Ea)
• Leading to more frequent successful collisions

Question 16

everyday catalysts

Answer 16

• Nickel
• Iron
• Platinum
• Vanadium oxide
• Hydrochloric acid