What is a titration?

Titrations are used to make soluble salts (remember solubility rules) from an acid and an alkali. There are no solids involved in this reaction and the solutions made are colourless so there is no way of telling when the reaction has finished. But remember that acids and alkalis have different pHs (acids are less than 7 and alkalis are greater than 7). When they have reacted in equal amounts (where we want to get to) the pH is 7. The way to tell what the pH is is by using an indicator such as methyl blue or phenolphthalein.The method required is as follows: measure out a set volume of alkali in a pipette using a pipette filler and put it in a conical flask. Add an indicator to the flask as well. Add acid to a burette and begin to add reasonably quickly to the conical flask. When the indicator changes colour, stop adding the acid and measure how much was added. Repeat this method, adding the acid more slowly this time, until you get concordant results (within 0.1cm^3). You now know the amount of acid that needs to be added to the alkali so can react them together to make the salt you want.Another use of titrations is to find the concentration of an acid or alkali by reacting it with an alkali/acid of known concentration and using mole calculations to work out what you need to know.