Describe a method you could use to separate a mixture of sand and sugar.
Basically, the mixture of sand and sugar can be separated based on radically different solubility of those components in water. Find out detailed information here http://www.ehow.com/how_5132916_separate-mixture-sand-sugar.html.
Add water to the mixture. Therefore dissolving the sugar and leaving the sand.
Wat richgrav said, wen u add water, the sugar dissolves and u r just left with the sand