Rate Of Reaction Experiments

Question 1

How can you measure how surface area affects rate of reaction

Answer 1

Using marble chips and hydrochloric acid
Use a gas syringe to measure the volume of gas produces at regular time intervals
Repeat the experiment using exactly the same volume and concentration of acid
And the exactly the same mass of marble chips but more crunched up
Then repeat with the same mass of powdered chalk
Finer particles result in a higher rate and a greater concentration of acid result in a higher rate

Question 2

How can you measure how temperature affects rate of reaction

Answer 2

Sodium thiosulfate and hydrochloric acid react to form a yellow precipitate
Measure the time it takes for the black mark beneath the flask they are in to disappear
To change temperature use a water bath to heat both solutions before mixing
Ensure the depth of the liquid is the same

Question 4

How can you measure how catalysts affect the rate of reaction

Answer 4

Decomposition of hydrogen peroxide
Manganese oxide catalyst speeds it up
Use a gas syringe to measure the volume of oxygen produced at regular time intervals
Repeat ensuring volume and concentration of hydrogen peroxide are the same but catalyst in use is different e.g. copper oxide or zinc oxide
Better catalysts result in an increased rate of reaction