British Sign Language Glossaries of Curriculum Terms

BSL Chemistry Glossary - distillation, boiling, condensation - Laboratory video

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Video: This is distillation. In this round bottom flask there is ink mixed with water. Water will go up the flask and adapter as steam, then down the condenser and drip into this beaker. Watch what happens. First I heat the solution until it boils. Water reaches boiling point at 100 oC. When it reaches that temperature it evaporates into steam. Then the steam comes down this condenser here. Inside is the steam and on the outside there is cold water going round – water is pumped in from the cold water tap via the rubber tubing. As the steam comes down the condenser it gets colder and condenses to water. Then it will drip into the beaker. It's boiling now and evaporating. You can see some condensation at the top of the glass tube where it starts to cool down. Now you can see the water dripping into the beaker. We have separated the water from the ink. The ink is still in the round bottom flask and this is pure, colourless water in the beaker.