Separation of Substances Notes

• A material which is made up of a particular kind is called a substance.
• It has mass and occupies space.

e.g.: chemical substances and other substances like salt, pure water, iron filings, etc.

Mixture:

• A mixture is a material of two or more different substances which retain their chemical properties.

e.g.: Soil is a mixture of clay, stones, plant & animal remains.

• The removal of substances from a mixture of two or more substances is termed as separation.
• Examples- filtering water, separating vegetables and fruits, sieving the flour, straining tea.
• If we observe the grains carefully; we will find tiny stones, insects, etc. in it which needs to be separated before consuming it.

Methods of Separation:

1. Foot threshing:

• In this process, threshing is done by using bare feet or animals to thresh the crop which is spread on the floor.

2. Manual threshing:

• In this process, the grains are separated from the straw by impact when the crop is beaten against a slatted bamboo; wooden platform or any other hard object such as steel oil drum.