Normally, after the tea is made, the leaves are separated by straining it through a strainer, or a clean piece of cloth. What you are doing is called filtration. The difference between filtration in a kitchen and the filtration in a laboratory is, that in the laboratory, we use a filter paper instead of using a strainer or a piece of cloth.. Filter paper is a special kind of paper, which has tiny pores of specific dimension, which allow only the liquid to pass through, whereas the undissolved solid particles are retained on the filter paper. The liquid passed through is called the filtrate while the undissolved solid particles are called the residue.
Experiment to separate powdered chalk from water
Take a round strip of filter paper. Fold it into half, and then into quarter. Then open it in the form of a cone and place in a funnel and fix it to the funnel with the help of a few drops of water.Take a small quantity of the mixture of water and powdered chalk. Transfer it with the help of a glass rod to the of filter paper cone, fixed to the funnel. You must take care to see that the level of water within the cone of the filter paper does not rise to more than three fourths of the filter paper. (Fig.4.6)
The clear water that passes out through the filter paper (filtrate) is collected in a clean beaker.
