Chemistry chapter 8 (Rate of Reaction)

Question 1

Define collision theory?

Answer 1

For a reaction between two particles to occur, the particles must collide and the collision must be effective

Question 2

Define effective collisions?

Answer 2

When the particles collide with enough kinetic energy and the correct orientation to break the bonds between particles so new bonds can form.

Question 3

What will happen if collision occurs with insufficient energy or incorrect orientation?

Answer 3

The particles will collide but no reaction will take palce

Question 4

Define rate of reaction?

Answer 4

The speed of the reaction

Question 5

When does reaction take palce?

Answer 5

When particles collide with a certain amount of energy with the correct orientation.

Question 6

What is the minimum amount of energy needed for the particles to react?

Answer 6

Activation energy

Question 7

What are the 2 things that the rate of reaction depends on?

Answer 7

1. The frequency of collisions between particles
2. The energy with which particles collide

Question 8

What factors influence the rate of reaction?

Answer 8

. Temperature
. The concentration of dissolved reactant
. The pressure of gaseous reactants
. Surface area
. Catalyst
. Light

Question 9

How can rate of reaction be meassures?

Answer 9

By measuring the change in the amount of reactant or product.

Question 10

How can the rate of reaction be calculated from a graph?

Answer 10

y/x

Question 11

How does temperature affect reaction rate?

Answer 11

The higher the temperature, the higher the reaction rate

Question 12

Explain how increase in temperature raises reaction rate?

Answer 12

At a higher temperature, particles have more kinetic energy, which leads to them colliding with each other more often

Question 13

How does the concentration of dissolved reactants affect rate of reaction?

Answer 13

The higher the concentration of the dissolved reactant the faster the rate of reaction.

Question 14

Explain how increase in concentration increases the rate of reaction.

Answer 14

At a higher concentration, there are more particles in the same amount of space. This means that the particles are more likely to collide and therefore more likely to react.

Question 15

How does the pressure affect the rate of reaction?

Answer 15

The higher the pressure the higher the rate of reaction

Question 16

Explain how pressure affects the rate of reaction?

Answer 16

As the pressure increases, the space in which the particles are moving becomes smaller while retaining the same number of particles. This increases the frequency of the particle’s collision.

Question 17

How does the surface area affect the rate of reaction?

Answer 17

The larger the surface area of the solid, the higher the rate of reaction.

Question 18

Explain how the surface area affects the rate of reaction?

Answer 18

The higher surface area means that there is an increased area where the particles could collide.

Question 19

What is the product of a metal carbonate + acid?

Answer 19

Salt + H2O + CO2

Question 20

What is the product of Metal + acid?

Answer 20

Salt + hydrogen

Question 21

What are catalysts?

Answer 21

Substances that speed up the rate of the reaction without being used up in the reaction.

Question 22

What is the relationship between catalysts and the amount of product?

Answer 22

Catalysts never produce more product, they just produce the same amount faster.

Question 23

How do most catalysts in a chemical reaction work?

Answer 23

Different catalysts work in different ways, but most lower the reaction’s activation energy.

Question 24

Most catalysts are —— ?

Answer 24

Transition metals

Question 25

Examples of catalysts and their uses?

Answer 25

. Nickel: A catalyst in the production of margarine
. Iron: A catalyst in the production of ammonia from nitrogen and hydrogen
. Platinum: A catalyst in the catalytic converters of car exhausts. It catalyses the conversion of carbon monoxide and nitrogen oxide into carbon dioxide and nitrogen

Question 26

Why are catalysts so important for industries?

Answer 26

Products can be made more quickly saving time and money

Question 27

How do catalysts save money for industries?

Answer 27

Catalysts reduce the need for high tempatures, saving fuel and reducing pollution

Question 28

What are biological catalysts?

Answer 28

Special types of proteins called enzymes.

Question 29

At what PH do most enzymes work best?

Answer 29

Around PH 7

Question 30

At what tempature do most enzymes start to get denatured?

Answer 30

Above 45 degrees celcious

Question 31

Define absorbtion in solid catalysts

Answer 31

When molecules are absorbed on the solid surface of the catalyst

Question 32

What does absorbtion in solid calatlyst do

Answer 32

It brings molecules closer together and weaken the bonds, making them react easily.