What volume of ethyl alcohol and water must be mixed together to prepare 250 ml of 60% volume by volume solution of alcohol in water.

Calculate the mass of potassium sulphate required to prepare its 10% solution in 100 g of water.

Differentiate between physical and chemical change. Give one example of each. Give one example where both physical and chemical change is taking place.

Mention any two differences between compounds and mixtures.

Which separation technique will you apply for separating the following mixtures:

(i) Butter from curd.

(ii) Different pigments from extracts of flower petals