The rate of a chemical reaction can be thought of as:
How quickly reactants are used up, or how quickly products form.
In this experiment we will be looking at how quickly magnesium reacts with dilute hydrochloric acid.
To carry out this investigation we need to consider several factors:
1) What will we change?
This is known as the Independent Variable – in this case you will change the concentration of the hydrochloric acid by diluting it with deionised water.
2) What will we measure?
This is known as the Dependent Variable – it will depend on the changes we make. We will measure the time it takes for the magnesium to react fully with the acid.
3) What will we keep the same?
These are known as Controlled Variables – these are factors which would affect the rate of the reaction if they were not kept the same. In this case we need to:
Use the same volume of solution.
Use the same mass of magnesium.
Use the same temperature of reaction.
Use the same particle size of magnesium.
Safety considerations - follow safety advice given by your teacher.