F322-Rates Of Reaction

Question 0

What 5 key factors change the rate of a reaction?

Answer 0

Temperature
Pressure
Surface area
Catalyst
Concentration

Question 1

Describe what happens to the rate of reaction over time

Answer 1

As the reaction proceeds, the reactant particles are used up, and their concentration decreases. Therefore, there are fewer collisions and a smaller number of successful collisions per unit time.

Question 2

What temperature increases the rate of reaction?

Answer 2

A higher temperature

Question 3

Does a catalyst increase the rate of a reaction?

Answer 3

Yes

Question 4

Does the rate of reaction increase with smaller of larger pieces of reactants?

Answer 4

Smaller pieces

Question 5

Does a high or low concentration increase the rate of reaction?

Answer 5

High concentration

Question 6

What must particles do to react?

Answer 6

1-collide in the right orientation

2-have enough energy to break bonds

Question 7

Define Activation energy

Answer 7

The minimum energy required to start a reaction by the breaking of bonds

Question 8

Define rate of reaction

Answer 8

The change in concentration of a reactant or product per unit of time

Question 9

What types of reactions are affected by changes in pressure?

Answer 9

Gas Reactions

Question 10

Use collision theory to explain how increasing the pressure of the reactants affects the rate of reaction

Answer 10

The greater the pressure, the faster the reaction. This is because there are more particles per unit volume, therefore there a greater number of collisions and more successful collisions per unit time

Question 11

Use collision theory to explain how increasing the temperature affects the rate of a reaction.

Answer 11

An increase in temperature increases the rate of reaction. This is because at higher temperatures there are a greater number of particles with energy that is higher than the activation energy. Therefore, there will be a greater number of successful collisions per unit time

Question 12

Catalysts are able to speed up reactions by..

Answer 12

Providing an alternative reaction route

With a lower activation energy

Question 13

Explain how the catalyst speeds up the decomposition of Nitrogen(II) Oxide

Answer 13

• reactant molecules are adsorbed onto the surface
• reaction occurs on the surface (bonds are weaker)
• product molecules are desorbed

Question 14

Explain why catalysts have a large surface area

Answer 14

It increases the rate of the reaction

Question 15

Why is it important to remove NO from car exhaust gases?

Answer 15

Because it is toxic & acidic so contributes to acid rain

Question 16

Name a catalyst used in the chemical industry

Answer 16

Nickel catalyst used in hydrogenation to make margarine

Question 17

What type of catalyst does the Haber Process use? & what is the use?

Answer 17

Iron catalyst

Used to fertilise plants

Question 18

What is cracking used for?

Answer 18

Making useful short alkenes & alkenes

Question 19

What effect does a catalyst have on the rare of reaction? How does it achieve this effect?

Answer 19

A catalyst speeds up a reaction by providing an alternative route with a lower activation energy.
The reaction is faster as a greater number of particles have an energy that is higher than the activation energy. So there will be a greater number of successful collisions per unit time.

Question 20

Catalytic converters use what catalyst?

Answer 20

Platinum, palladium or rhodium catalyst (heterogeneous catalyst)

Question 21

What catalyst does cracking use?

Answer 21

Aluminium Oxide catalyst (heterogeneous)