Let us divide the class into groups A, B, C and D. Group A takes a beaker containing 50 mL of water and one spatula full of copper sulphate powder. Group B takes 50 mL of water and two spatula full of copper sulphate powder. Groups C and D can take different amounts of copper sulphate and potassium permanganate or common salt (sodium chloride) and mix the given components to form a mixture. Compare the colour of the solutions of the groups A and B.

Let us divide the class into groups A, B, C and D. Group A takes a be

1.	Let us divide the class into groups A, B, C and D. Group A takes a beaker containing 50 mL of water and one spatula full of copper sulphate powder. Group B takes 50 mL of water and two spatula full of copper sulphate powder. Groups C and D can take different amounts of copper sulphate and potassium permanganate or common salt (sodium chloride) and mix the given components to form a mixture. Compare the colour of the solutions of the groups A and B.
Answer» Solution :The INTENSITY of colour of the solution is different. This shows that a homogeneous MIXTURE can have a variable composition. Groups C and D have obtained mixtures, which contain physically distinct PARTS and have non-uniform compositions. Such mixtures are called heterogeneous mixtures. Mixtures of (a) sodium chloride and iron filings (b) salt and sulphur ( c) OIL and water are the examples of heterogeneous mixtures.