Select homogeneous and heterogeneous mixture from the following:

Salt solution, petrol and water, sand and charcoal, alcohol and water, air dissolved in water, seawater, fruit juices, mist and brass.

Explain the following with examples:

Pure substance

Define an impure substance with an example.

Define alloy with an example.

Define solution with an example.

Define a heterogeneous mixture with an example.

Define a homogeneous mixture with an example.

Give reason:

Why do sugar and water retain their individual properties in a sugar solution?