How to Separate Sugar & Salt Crystals

Ah, the sweetness of sugar...

On the face of it, this seems the easiest task imaginable. Just taste the mixture: salt tastes salty and sugar is sweet. However, if you follow this route, you would have to consume all the mixture to know which of the crystals are salt and which are sugar. At a microscopic level, sugar and salt look different, but to the naked eye, table salt and table sugar look about the same. Fortunately, there are ways of separating salt and sugar crystals. Be aware, though, that the separated crystals will not be edible.

Things You'll Need

• Salt
• Sugar
• Water
• Ethanol/petroleum spirit
• Fine mesh filter
• Heavy-bottomed pan

Instructions

Method One---Dissolve Sugar

1. Add a small amount of ethanol to the sugar and salt mixture. Sugar will dissolve in ethanol, whereas salt will not.

2. Filter the solution. The salt crystals stay in the filter while the sugar solution passes through.

3. Leave the solution to evaporate. The sugar crystals will reappear.

Method Two---Burn Off Sugar

1. Put the salt and sugar mixture in a heavy-bottomed pan.

2. Cook for about thirty minutes on high heat till the sugar burns away.

3. Take the salt left on the bottom. If there is soot from the burnt sugar, dissolve the mixture in water.

4. Filter out the soot.

5. Evaporate the water to recover the salt.

Tips & Warnings

• Handle ethanol carefully.

• Be cautious when heating the sugar.

References

• MadSciNetwork: Chemistry: How do you separate salt and sugar if accidentally mixed together?
• The Gateway to Discovery: Crystal Science Projects