As part of their unit on Chemistry the year 8 science students are looking at the difference between Physical and Chemical Change. Physical changes involve the matter changing form but not creating new substances and melting, boiling and sublimation (phase changes) are good examples of this phenomena.

Students where able to investigate dry ice (frozen carbon dioxide) and its properties by looking at some interesting demonstrations including handling dry ice pellets (carefully!), adding the pellets to water and looking at the effect of water vapour forming and the escaping gas being heavier than air and sinking to the floor. A large carbon dioxide bubble was also formed and students could experience foam formed from the gas bubbled into a mixture of water and detergent.

A chemical change reaction was also demonstrated as the dry ice was added to a basic
solution with universal indicator and there was a series of spectacular colour changes as the substance turned into an acid.