Topic 6: The Rate and Extent of Chemical Change

Question 1

How is rate of reaction calculated?

Answer 1

Rate of reaction = amount (e.g. grams, cm3) of reactant used or product formed/time

Rate of reaction (mol/s) = Moles of reactant used or product formed/ time

Question 2

How does pressure change the rate of reaction?
Example N2 + 3H2 == 2 NH3

Answer 2

1. You need to look at number of moles
2. Where there are less moles, the pressure favours it.
   Example N2 + 3H2 == 2 NH3

There are 4 moles on the right vs 2 on the left. More NH3 will be produced