Methods of Separation in Everyday Life: common misconceptions

If your child says… “If I can see different colours, handpicking is always convenient.”

Ask together

How many separate picks would a huge heap need?

What’s true

The pieces must also be few and easy to grasp.

If your child says… “Beating gets rid of the loose husk too.”

Ask together

After beating, what will carry the loose husk away?

What’s true

Freeing grains and carrying loose husk away need different actions.

If your child says… “Shake harder and everything will pass through.”

Ask together

Can this whole stone fit through that opening?

What’s true

Shaking cannot make a whole stone fit through a smaller hole.

If your child says… “The salt would disappear with the water.”

Ask together

If salt stayed behind, what would you find on the dry plate?

What’s true

Salt does not evaporate with water under these conditions.

If your child says… “Pouring off must remove every solid.”

Ask together

What blocks a grain that starts moving with the water?

What’s true

Some particles can travel with the poured water.

If your child says… “Every filter catches the same bits.”

Ask together

Would smaller openings catch some particles these openings let through?

What’s true

Particles smaller than a filter’s openings can pass through.

If your child says… “The floating part is buttermilk.”

Ask together

Are the floating lumps butter or buttermilk?

What’s true

The floating lumps are butter, with buttermilk beneath.

If your child says… “Magnets can separate any two solids.”

Ask together

If neither material moves towards the magnet, what could it remove?

What’s true

A magnet cannot separate materials that it attracts equally.