Topic 4 - Introduction to Kinetics

Question 1

How does a chemical reaction occur?

Answer 1

When particles of substances collide and have energy equal to or greater than the activation energy of the reaction and the particle orientation must be correct

Question 2

What`s activation energy?

Answer 2

The minimum energy that gaseous reactant molecules must possess to undergo a reaction.

Question 3

What is a Maxwell-Boltzmann curve?

Answer 3

A plot of number of gaseous molecules against the energy they have

Question 4

What does the area under the graph represent in an M-B curve?

Answer 4

The total number of molecules in the sample

Question 5

What is rate of reaction?

Answer 5

A measure of the change in the concentration of a reactant or product with respect to time.

Question 6

What`s the effect of temperature on rate of reaction?

Answer 6

• Increases rate of reaction
• Increases kinetic energy of reacting particles
• Which leads to an increase in the frequency of collisions and frequency of successful collisions.

Question 7

How does a Maxwell-Boltzmann curve change at increased temperature?

Answer 7

Shifts to the right so that a greater proportion of molecules have energy equal to or greater than the activation energy.

Question 8

What`s the effect of increasing pressure on rate of reaction?

Answer 8

• Increases rate of reaction
• Pushes the reacting particles closer together
• Leads to increase in frequency of collisions and frequency of successful collisions

Question 9

What`s the effect of increasing temperature on rate of reaction?

Answer 9

• Increases rate of reaction
• Increases the number of reacting particles
• Leads to an increase in frequency of collisions and frequency of successful collisions

Question 10

How does a catalyst work ?

Answer 10

By providing an alternative reaction route that has a lower activation energy.