Kinetics

Question 1

What is the equation for rate of reaction?

Answer 1

Change in concentration / time

Units: moldm^-3s^-1

Question 2

What is activation energy?

Answer 2

Minimum amount of kinetic energy the particles need to react

Question 3

What is a catalyst?

Answer 3

Substance that speeds up the rate of reaction that is chemically unchanged at the end of the process

Question 4

What is a Maxwell-Boltzmann distribution?

Answer 4

The distribution energy among the molecules of a gas in a closed system

Question 5

What does the area underneath the curve in a MB curve show?

Answer 5

Total number of particles present

Question 6

If you decrease the temperature, what do you expect the MB curve to look like?

Answer 6

Taller peak and narrower overall

Question 7

If you increase the temperature what do you expect the MB curve to look like?

Answer 7

Shorter peak and wider overall

Question 8

What happens to the MB curve when you add a catalyst?

Answer 8

No change to curve, only change overall is Ea is lower

Question 9

What factors increase the rate of reaction?

Answer 9

Increase in concentration (liquids)

Increase in pressure (gas)

Increase in surface area

Increase in temperature

Addition of a catalyst

Question 10

What is the collision theory?

Answer 10

Reactions only occur when collisions take place between particles with sufficient energy.

The energy is usually needed to break the relevant bonds in one or either of the reactant molecules

Question 11

Explain the economic importance of catalysts

Answer 11

Catalyst provides a different reaction pathway with a lower activation energy so reaction requires less overall energy and therefore costs are lower.