Rates of chemical reactions

Question 1

What is the rate of a chemical reaction?

Answer 1

Change in concentration

Question 2

How can rate of reactions be measured?

Answer 2

-Mass loss
-Volume
-Time taken for colour/PH to change
-Concentration change

Question 3

What are the 3 things that must occur for a reaction to take place?

Answer 3

-particles must collide
-collide with sufficient energy
-collide with correct orientation

Question 4

What does the transition state refer to ?

Answer 4

When the activation energy is absorbed
-this is an unstable state

Question 5

Ways to alter the rate of reaction?

Answer 5

• surface area of solid reactant
  -concentration of reactant solution
  -gas pressure
  -temperature
  -presence of a catalyst

Question 6

How can you increase the energy of collisions?

Answer 6

Increase temperature and kinetic energy

Question 7

How can you increase the frequency of collisions?

Answer 7

Increase concentration(liquid) or pressure (gas)
Increase surface area of solid

Question 8

What do catalysts do?

Answer 8

increase rate of reaction by providing an alternative pathway with a lower activation energy

Question 9

A homogeneous catalyst is….

Answer 9

in the same state as the reactants and products

Question 10

A heterogeneous catalyst is ..

Answer 10

in a different state then the reactants