Having learned all about rocks and soils the pupils of fourth and fifth class did further investigations during their Science classes.
Three pupils brought in samples of soil from their farms at home to examine closely the ingredients of their soil.
- Clay • Sand • Silt • Humus or organic material
They discovered this when they filled a glass jar with 1/3 soil and the rest of it with water.
They shook each of the jars and allowed time for the soil to settle.
The pupils discovered the following
- The heavy sand sunk to the bottom.
- The lighter silt settled on top of this
- The lightest ingredient, the clay settled on the top.
- The humus or organic material floated to the surface.
Following their experiment there was much speculation about which soil was the best soil for farming in Doohamlet!
The study of rocks would not be complete without exploring crystals. Most solids are made up of lots of crystals. Sometimes you cannot see them because they are too small or are stuck together. Diamonds are probably the most beautiful crystals of all.
The Pupils got some bread soda and cream of tartar with 50ml of cold water. They followed these instructions to make their own crystals:
- Put one level teaspoon of bread soda into a plastic container.
- Add about50 ml of water and stir well.
- Add one level teaspoonful of cream of tartar and stir well. The two chemicals react together to form Rochelle salt
- Add a second level teaspoonful of cream of tartar and stir well.
- Repeat with a third level teaspoonful of cream of tartar and stir well
- To make sure the reaction has fully taken place put the container into a shallow bowl of hot tap water.
- Some solid will be left on the bottom.Leave the solution in a cupboard for several days for the water to evaporate and you should gets some crystals of Rochelle Salt.
Growing Crystals takes time but the crystals are worth it !