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Aim: This is to illustrate some features of how bases react.

Equipment: The equipment includes...  

• large glass.
• ice cream.
• lemonade.
• stirrer.

Method: Pour lemonade into a large glass. Prepare icecream in a spoon in small pieces (to increase the amount of surface area that can react with the icecream) and then mix it in well with the lemonade using the stirrer.

Background knowledge: The lemonade has dissolved sodium carbonate in it. This makes the mixture basic (the opposite to acidic). Acids tend to give off charged hydrogen ions. The more they give off the more dangerous they are. Bases tend to absorb charged hydrogen ions and in just the same way can be dangerous. The reaction of a base and acid causes all the fizz. There is a huge amount of carbon dioxide gas given off (ie. the fizz). By breaking up the icecream before adding lemonade and then stirring really quickly speeds up the reaction and makes it froth more.