British Sign Language Glossaries of Curriculum Terms

BSL Chemistry Glossary - separation, dissolve, evaporation, filtration, soluble, insoluble - Laboratory

Note: this is a very long movie so please allow it time to load.

Here we have two jars - one containing sand, the other salt and what I'm going to do is mix them together. So now we have a mixture of salt and sand - we haven't created a new material, it's just sand and salt mixed together.

However, it is possible to separate them - let me show you how. I'm going to pour in some water and I'm doing that because I want to dissolve the salt - salt is soluble whereas sand isn't - it's insoluble.

Next I'm going to extract the salt using filter paper (filtration) and can you see coming out of the bottom is a colourless liquid and that's the water and salt solution. Have a look at the top of the funnel ... now the salt is still there - let me show you.

I'm going to get rid of the water by evaporating it using the heat from this bunsen burner. As the water boils it's giving off steam and evaporating and as it does so you can see this white powder emerging.

Now the salt and sand have been separated - in the dish you can see just the salt and the sand is here in the filter paper, both the sand and the salt have been separated.