Question

When is separation of substances necessary? Name four methods used to separate would substances ​

Answer 1

Explanation:

Separation is necessary when we want to remove unwanted things from a mixture. This also helps us to obtain the required substances. Four methods to separate solid substances are : Threshing, Winnowing, Hand-picking and Sieving.

Answer 2

Answer:

There are three main reasons why we need to separate mixtures.They are:

1) To remove unwanted particles

A bhel is a mixture of various ingredients like onion, tomato, potato, chillies, etc. Someone who does not like spicy food will remove the chillies to prevent mouth burn. Therefore, separation is necessary to remove the chillies from food.

Your mother always removes stones from rice before she cooks. Because stones are not wanted. Separation is necessary to remove the stones.

Also, your mother removes the tea leaves from tea using a strainer. We cannot drink tea with the tea leaves. Hence, they are separated.

Air also contains dirt and dust.We have hair in our nostrils which separate the dust and dirt particles from the air.

Did you know that the water we drink comes from rivers and lakes? But it contains impurities and germs. They are not wanted. Thus, Separation is necessary to remove these impurities.

Methods Of Separating Mixtures

Some of the common methods of separating substances or mixtures are:

Handpicking

Threshing

Winnowing

Sieving

Evaporation

Distillation

Filtration or Sedimentation

Separating Funnel

Magnetic Separation

Explanation:

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