Unit 2-Kinetics

Question 1

What are four factors which affect the rate of reaction?

Answer 1

• Temperature
• Pressure/Concentration
• Surface area
• Catalyst

Question 2

What is the Maxwell-Boltzmann distribution and what does it show?

Answer 2

• A distribution which shows the poportion of molecules with their energy
• The area shows the proportion of molecules with the required avctivation energy
• An increase in temeprature causes the distribution to increase in area and gives more molecules with the required activation energy
• A catalyst also shifts the distribution so that more molecules have the required activation energy

Question 3

How does pressure/concentration lead to an increased rate of reaction?

Answer 3

• Increased pressure/concentration decreases the volume
• More molecules in a smaller space
• More collisions thus an increase in rate

Question 4

How does surface area increase the rate of reaction?

Answer 4

• More solid pieces in smaller pieces
• Leads to a greater surface area
• More collisions occur
• Increased rate of reaction

Question 5

How does temperature increase the rate of reaction?

Answer 5

• More KE for molecules
• Leads to more succesful collisions
• That have the correct orientation and required activation energy
• Faster rate of reaction
• At higher temperatures, more molecules have the required activation energy

Question 6

How does a catalyst increase the rate of reaction?

Answer 6

• A catalyst works by providing an alternative pathway
• The alternative pathway has a lower activation energy
• Therefore more molecules have the required activation energy
• Can work by bonding with the reactant to form an intermediate which breaks down forming the product