Materials and their Properties
Throughout the Autumn term Year 5 and 6 have been exploring materials and their properties during their Science lessons. The children have been developing and using their scientific language throughout this topic whilst they have been learning about solids, liquids and gases, and changes of state. They have also been investigating how different materials have different properties such as their hardness, conductivity and thermal qualities, how some dissolve and how others are insoluble. They have also been discovering how some changes are reversible and how others are irreversible.
To demonstrate reversible processes the children investigated heating up materials, separating mixtures, evaporation and condensing.
For heating (melting) as a reversible process pebbles were heated up in the oven and carefully placed crayons were placed onto the pebbles and the children observed what happened. They noticed that the solid wax crayons soon melted when they touched the hot pebbles. They chose to use a variety of colours and when the pebbles cooled they noticed that the wax had become a solid again and the process had created some amazing effects.
Investigating irreversible changes was quite tasty as the children mixed eggs, flour, butter and sugar to make fairy cakes and learned that a cooked egg could not be reversed back into a raw egg and that baking this mixture was irreversible. Yum! They also discovered that by mixing some liquids and solids a chemical reaction would take place to produce a new material. They watched carbon dioxide being produced when vinegar and bicarbonate of soda reacted with each other. It was effervescent.