Titration Method

A titration is a scientific experiment designed to determine the concentration of an unknown acid or base. You can determine its approximate pH with litmus paper, but you cannot determine concentration, so you need the titration method to find out how strong the solution is.

Materials Needed

To do a titration, you need a burette, beaker, indicator and an opposite solution. For example, if the unknown solution was an acid, you would need a base to neutralize it.

Indicator

The indicator is a liquid that will change the color of the liquid when the unknown solution is neutralized. Different indicators work for different pH levels. For example, if you know the pH of the unknown solution is around five, you would use methyl red.

Setup

Pour the unknown solution into the beaker and the known solution into the burette. Add a few drops of the indicator to the beaker and set up the burette above the beaker.

Procedure

Allow the solution in the burette to drip into the beaker. When the color of the solution changes, you know the solution has been neutralized and the experiment is complete.

Calculations

Multiply the volume of the known solution used by the concentration, then divide by the volume of the unknown solution to get the concentration. For example, if you used 40 ml of a 2.0 M base to neutralize 50 ml of an unknown acid, the concentration would be 1.6 M.

References

• Titration Method