Exploring Mixtures and their Separation: common misconceptions

If your child says… “If the water looks clear, it must be pure.”

Ask together

What did we add that we can no longer see?

What’s true

Clear salt water contains both water and dissolved salt.

If your child says… “I divide by the water alone.”

Ask together

Does sugar add to solution mass?

What’s true

Include both sugar and water.

If your child says… “Crystals appear only after all the water dries up.”

Ask together

Does the cooler beaker still contain water?

What’s true

Crystals can form while water remains.

If your child says… “Alum filters the mud out.”

Ask together

Where is a filter in the alum row?

What’s true

Alum helps particles clump, then settling separates them from the water above.

If your child says… “Milk is a true solution because it looks even.”

Ask together

If both look even, why does only one reveal the beam?

What’s true

Milk has larger particles than a true solution, so it scatters light.

If your child says… “Water always floats on top.”

Ask together

Which liquid lies below the other in this funnel?

What’s true

Mustard oil is less dense than water, so water forms the bottom layer.

If your child says… “Distillation collects only what stays in the pot.”

Ask together

What carries water into the receiver?

What’s true

Collected water comes from cooled vapour.

If your child says… “The ink spot should go underwater.”

Ask together

Where would the ink go if we dipped the spot itself?

What’s true

A submerged spot washes into the water instead of travelling up the paper.