Separating Salt and Sand
In this experiment you will separate a mixture of sand and salt, illustrating the fundamental
means of separating a physical mixture of an insoluble material from one which is soluble.
Materials
Eye protection
250 mL beaker
Funnel
Filter paper
Evaporating dish
Hot plate
20% salt and sand mixture
Procedure
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Pour 7 g of the sand-salt mixture into the beaker so that it just covers the base.
Add 25 mL of water.
Swirl the mixture gently for a few minutes.
Filter the mixture into the second 250 mL beaker.
Pour the filtrate into an evaporating basin.
Heat the salt solution gently until it starts to decrepitate (“spit”).
CAUTION: Keep eye protection on and do not get too close.
7. Turn off the hot plate.
Lab Questions
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Why can sand and salt be separated using this experiment?
Why is the salt, sand and water mixture swirled in step 3?
Why is the salt solution heated in step 6?
How might the final traces of water be removed from your samples to ensure that they’re
totally dry?
Give two reasons why the sand you have obtained might still be contaminated with salt.
How could you adapt your experiment to obtain a purer sample of sand?
Give two reasons why the salt you have obtained might still be contaminated with sand.
How could you adapt your experiment to obtain a purer sample of salt?