Question

4. Give scientific reason for the following:
a) Obtaining Alum crystals from Alum solution is physical change.

b) We can not recover Iron from rust.

Answer 1

Answer:

a) Alum is not soluble in water . It increases the power for the sedimentation to take place, That's why it's a physical change because there is no change is the chemical composition of Alum.

b) Yes , because the properties of Rust and Iron are entirely different . Rusting is a chemical change and Thus we cannot get back the same iron form.

Explanation:

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