Kinetics

Question 1

Give examples of fast rates of reaction?

Answer 1

Decomposition of TNT

The combustion of fuel in the cylinder of a car engine

Question 2

Give examples of slow rates of reaction?

Answer 2

Rusting of fuel

Question 3

What is rate of reaction?

Answer 3

Is the number of moles of reactant that is used up or the number of moles of a product is produced in the set time

Question 4

Equation of rate of reaction?

Answer 4

Amount of reactant that is used or
the amount of product formed
Rate of reaction = ——————————————————-
Time

Question 5

What are the 4 factors that can be used to increase the rate of reaction?

Answer 5

[Increasing Temperature]

• If you increase the temperature of a reaction, the particles will on average have more kinetic energy and move faster
• As particles fly about faster they will collide more often. This causes an increases the rate of reaction

[Increasing Pressure]

• If you increase the pressure when reaction involves in gas.
• As a result, this pushes all gas particles closer together. Making them more likely to collide. So collisions take place more frequently and reaction rate increase

[Increasing Concentration]

• If you increase the concentration of reactants in a solution, the particles will on average be closer together.
• If they’re closer, they will collide more often. If collisions occur frequently, they’ll have more chances to react (as a result increasing rate pf reaction)

[Using Catalyst]

Question 6

What is a catalyst? How does it increase the rate of reaction?

Answer 6

Catalyst is a substance that increases the rate of reaction by providing an alternative reaction pathway with lower activation energy. The catalyst is chemically unchanged at the end of the reaction.

Question 7

What is collision theory?

Answer 7

Is the idea that for a reaction to take place, particles must collide…

Question 8

What is activation energy?

Answer 8

Is the minimum energy needed by colliding molecules for them to react. The energy is then transferred enables bonds in the reactants to be broken before new ones can form in the products

Question 9

What does the Maxwell-Boltzmann Distribution Energies tell us?

Answer 9

It enables us to describe the relationship between kinetic energy and activation energy

It allows us to explain which proportion of collisions are effective.

Question 10

What causes effective collision to happen?

Answer 10

When molecules have kinetic energy greater than activation energy

Question 11

What does the shaded region of the Maxwell-Boltzmann Distribution Energies tell us?

Answer 11

It shows the proportion of molecules that have sufficient energy to react on collision {providing that they are correctly orientated}