How to make Sherbet

 

Making sherbet is a great practical activity to show students the action of an acid on a carbonate.

When acids react with carbonates like bicarb of soda, carbon dioxide gas is produced.

General equation: Acid + metal carbonate → salt + water + carbon dioxide gas

 

Method:

  1. Grind 2 tablespoons of sugar with ½ teaspoon of citric acid in a clean mortar and pestle.
  2. Add 2 tablespoons of icing sugar, 2 teaspoons of flavoured jelly crystals and ½ teaspoon of bicarb of soda. Mix together.
  3. Place the mixture into a plastic locking bag and shake. Eat with a paddle pop stick.

 

Questions: 

 

What puts the whiz in your fizz?

Citric acid + bicarb of soda → sodium citrate + water + carbon dioxide

 

HX     +  NaHCO         → NaX                 + H2O    +  ___________

 

Which compound contains the carbonate group? _____________

 

The fizz is produced by the action of an _____________ (anagram: cida) on a carbonate.

 

____________  ____________ gas is produced.

 

This is the gas that puts the whiz into your fizz!