British Sign Language Glossaries of Curriculum Terms

BSL Chemistry Glossary - titration - Definition

We use titration to help us to find the unknown concentration of an acid - acid can be found in different concentrations; we can identify that concentration using this process (Titration).

We also need some Universal Indicator which will change colour as we add the alkali from the burette into the conical flask below. As we open the tap and add the alkali we need the Universal Indicator otherwise we won't see anything happen.

You can see the Universal Indicator turns red when we add it to the acid which in this example is pH1.

What we want to do is very carefully open up the tap and add more and more alkali until the acid is neutralised = pH7 at which point we will see the Universal Indicator change colour ...

(01:40) As you can see it hasn't changed colour yet ...

(02:02) There - did you notice how quickly it changed to neutral? If we want to know how much alkali was added we can measure it by checking the volume that has dropped in the burette, which was 24.8 cm³>. The colour change is how we know when to stop. If we'd carried on and missed the end point, look what happens - we end up with too much alkali.