Prediction I predict that the higher the concentration of the acid the more alkali will be needed to neutralise the acid.
Hypothesis an equal amount of the same strength acid and alkali will neutralise each other, so if there is 100ml of 1 mole acid and 100ml of 1 mole alkali mixed together the solution would become neutral.
Variables the variables are:
The strength of the acid.
This will affect the amount of alkali needed to neutralise the acid, the stronger the acid the more alkali will be needed.
The strength of the alkali.
This will affect the amount of alkali that will be needed to neutralise the acid. If the alkali has a concentration of 2 mole and the acid has a concentration of 1 mole only half the amount of alkali would be needed to neutralise the acid.
The amount of the acid.
The more acid there is the more alkali will be needed to neutralise it.
This is because the volume of acid has increased therefore the volume of alkali needed to neutralise it will need to increase.
I have chosen to use universal indicator as this gave me the best results in my preliminary work. I am using an acid with a concentration of 2 mole
and an alkali with the strength of 1 mole, this means that it should take 40ml of alkali to neutralise 20ml of acid. I am using these different strengths of acid to get a varied set of results.
2.0 mole
1.7 mole
1.5 mole
1.0 mole
0.5 mole
I am using 20ml of acid.
Diagram
Method
1)Set up equipment as shown in the diagram.
2)Add alkali to the acid until the indicator shows that it is neutral.
3)Record the results in a table.
4)repeat the experiment using a different concentration of acid.
Safety wear safety goggles to protect eyes.
Results
Conclusion I have came to the conclusion after carrying out this experiment that, the higher the concentration of acid, the more alkali is needed to neutralise it. This conclusion supports my hypothesis and prediction.
