Aluminium
The Blast Furnace
Purification of Copper
Crude Oil
Electrolysis
Analysing Gases
Haber Process
Solubility of Salts
Steel
Test for Anions
Test for Cations
Titration

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Applied
Fundamental
Inorganic
Organic
Physical

Titration

The process of titration is used to calculate the concentration of a solution by neutralising it and doing some maths (all explained below).

The Process

the process of titration

Measure 10cm3 of acid using a pipette for accuracy. Then release it into the conical flask.
Add a few drops of indicator (in this example, phenolphthalein) to the conical flask
Fill the burette to the top indicator with sodium hydroxide solution
Put the conical flask on top of a white tile, this makes it easier to notice any colour change. Open the burette so the NaOH slowly flows/drops into the conical flask.
Swirl the conical flask. Towards the end the solution turns pink but when swirled, returns to colourless. Now add the NaOH dropwise. Now turn off the burette as soon as the pink doesn't disappear.
Record the amount of NaOH used.
Repeat the experiment to get concordant (the same) results.

Calculating Concentrations

Say that these were your results:

The most important thing to know when doing this calculation is this triangle, all further calculations are based on this.

triangle used to calculate concentration, moles or volume, with units

Now to continue we need the balanced equation for this reaction

HCl + NaOH NaCl + H2O

From the reaction, we can see that for every 1 hydrochloric acid there is one sodium hydroxide, so their moles are the same. Given that we have the concentration and volume of HCl, we can work out the number of moles. It is divided by 0.01 since there are 1000 cm3 in 1 dm3.

Now we have the moles of sodium hydroxide and also the volume we can work out the concentration.