Salt and Sand

Separating Salt and Sand
This is a popular experiment/investigation. Can the children think how to separate a mixture of salt and sand? If you do this at the end of a unit of work on separating materials then they certainly should be able to figure out that if you add the salt/sand mix to water then the salt will dissolve in the water. The sand can be extracted by filtration and the salt solution left can be heated to evaporate the water and leave the salt behind (this is best done by putting the salt solution in a dish over a pan of boiling water).

Possible frames for reporting on the experiment are given below - an open task sheet for the more able and a closed task sheet for those who need more support

Challenge: Separating salt and sand

What problem did we have to solve?

We had to try and see if we could..

What apparatus did we use to solve our problem?

We decided to use...

(Draw a diagram of the apparatus)

What did we actually do to solve our problem?

First of all we...

What Science did we use? Why did our solution work?

We knew that our solution would work because we knew that..

funnel	heated	filtering	filter
paper	bowl	boiling	evaporated	separate
salt	sand	beaker	water	Dissolve

Challenge: Separating salt and sand

What problem did we have to solve?

We had to try and see if we could separate ______ and _____ after they had been ________ together.

What apparatus did we use to solve our problem?

We decided to use...

(Draw a diagram of the apparatus)

What did we actually do to solve our problem?

First of all we put the salt and sand in a ________. We added ______ to the beaker to __________ the salt.

We poured the mixture through a ________ _______ into another beaker. The _______ got trapped by the _______ ________ and the _____ solution went through into the beaker.

We poured the salt solution into a ______ and put that over a pan of _________ _________. The heat _________ the water and the ___________ was left behind.

What Science did we use? Why did our solution work?

We knew that our solution would work because we knew that salt _________ dissolved in water. We knew that we could _______ sand from water by ________. We knew that if we _______ the salt water solution then it would ________ and leave the ______ behind.

You may need some of these words to help you write up your experiment.

funnel	heated	filtering	filter
paper	bowl	boiling	evaporated	separate
salt	sand	beaker	water	Dissolve