Reaction Rates

Question 1

What is reaction rate?

Answer 1

The rate of a chemical reaction is the speed at which the reactants are chemically converted into products.

Question 2

What is Collision Theory?

Answer 2

Collision Theory States that:

1.Particles must collide

2.Particles must collide in correct orientation

3.The particles must collide with sufficient energy

Question 3

Factors affecting Reaction Rate: (Nature of Reactants)

Answer 3

The reaction rate depends on the nature of reactants. A chemical reaction that has less bond breaking and bond forming will naturally be faster then a complex reaction.

Question 4

Reaction rate: Concentration

Answer 4

• Increasing the concentrations of reactants can increase the rate of chemical reaction.

-With more particles per unit volume, there is a increased frequency of collisions.

• This increases the proportion of particles that can have a successful collision with sufficient energy and with correct orientation.

Question 5

Reaction Rate: Pressure/volume

Answer 5

• Increasing the pressure or decreasing the volume can increase reaction rate.

-As the same quantity of particles are exposed to a smaller volume, they are closer to each other.

-Leads to more collisions, higher successful collision, hence inc reaction rate.

Question 6

Reaction rate: Surface area

Answer 6

Increasing the surface area increases the number of reactants particles exposed and available for collisions.

This increases the frequency of collisions between particles, and there are a greater proportion of particles colliding with the correct orientation.

Question 7

Factors Affecting Reaction: Agitation/stirring

Answer 7

• By creating movement in a fluid, reacting particles are more exposed for collisions, and are given more kinetic energy.
• more particles will have sufficient energy equal or greater then to the activation energy.

Question 8

Reaction rate: Temperature

Answer 8

• Temperature increases, particles vibrate and have more kinetic energy.

-They move at greater velocities and have more frequent collisions.

-More particles will have sufficient energy to react as well.

Question 9

Reaction rate: Catalyst

Answer 9

A catalyst is not consumed in a chemical reaction.

Provides an alternate reaction pathway of a lower activation energy.

More particles will have sufficient energy now to react.