Background Science
A titration is the neutralisation of an acid or an alkali. To achieve this, one must be added to the other in a specific amount, strength and concentration.
A substance is neutral when its pH is 7. It is most acidic closer to 0 and is most alkaline closer to 14.
28492453194050 0 7 14
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Acid Neutral Alkaline
Neutralisation occurs because:
Acid + alkali = salt and water
As both salt and water are neutral, the resulting chemical is neutral.
e.g. hydrochloric acid + sodium hydroxide = sodium chloride + water (HCL + NaOH = NaCl + H₂O)
Acidic solutions contain H⁺ (aq) ions. This H⁺ (aq) ion is removed from the solution when the acid is neutralised.
Alkaline solutions contain OH⁻ (aq) ions. This OH⁻ (aq) ion is cancelled out by the H⁺ (aq) ion.
e.g. H⁺ (aq) + OH⁻ (aq) = H₂O (l)
The acid and alkali are neutralised to make water.
An H⁺ ion is just a proton.
Acid reacts by giving protons (H⁺) and so are proton donors
Alkalis react by receiving protons and so are proton acceptors
Using this science, I conducted an experiment on how a specific factor affects the pH changes during a titration. I added a specific amount, type, and concentration of acid to an alkali until it neutralises.
The results of the experiment will produce a graph known as a pH curve. It shows the point at which the solution neutralises as the very steep part in the middle.
Factors that affect the pH curve
Factor Possible effect
Temperature May stimulate reaction.
Type of acid Strength varies in different acids. Stronger acid may result in shorter titration.
Type of alkali Strength varies in different alkalis. Stronger alkali