Page 111 - Science Class 6 Times Publication

Methods of separation

We use different methods to separate the components of different
mixtures. The choice of the method depends on the nature and
composition of the mixture. Some common methods for the separation
of mixture are discussed below.

Using a winnowing tray (Nanglo or Supo)

A winnowing tray is a circular concave disc which is made by weaving

the thin bamboo sheets. It is raised from the circumference so that it
can hold food grains inside it.

Activity 10.2

To prepare and separate the mixture of wheat grains and peas

Materials required

About 1 kg wheat grains, 200 grams peas and a winnowing tray.

Procedure
1. Mix about one kilograms of wheat
grains and about 200 grams of
peas in a winnowing tray.

2. Lift the winnowing tray little up
using both hands.

3. Move the tray right and left (in to and fro way) so that the
grains slide one over another.
Observation

The peas being round and smooth roll forward while moving the tray.
The wheat grains remain on the back position in the winnowing tray.

Conclusion
The pea seeds can roll whereas the wheat grains cannot. So, such
mixture can be separated using a winnowing tray. But it is dif cult
to separate rice and wheat grains by this method.

Times' Crucial Science and Environment 107 Book 6