The Effect of Acid on the Neutralisation Point
Aim to find how the concentration of acid affects the neutralisation
point between acid and alkali.
Preliminary work in my preliminary work my aim was to find out which
indicator would give the best results in my neutralisation experiment
to do this we used three different indicators and worked out which one
gave us the result closest to the neutralisation
point. We found that
universal indicator gave us the most varied results and was the
closest to the neutralisation point.
Prediction I predict that the higher the concentration of the acid
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
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.
I am using 20ml of acid.
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.
Concentration of acid (mole)
needed to acid (ml)
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