Which of the following are physical changes and which are chemical changes?

(a) Burning of a magnesium wire

(b) Freezing of water

(c) Rusting of iron

(d) Glowing of an electric bulb

9.72 g of potassium chloride dissolves in 30 g of water at 70°C. Calculate the solubility of potassium chloride at that temperature.

Classify the following as physical or chemical changes:

(i) Cooking of food

(ii) Boiling of water

(iii) Cutting of trees

(iv) Dissolving salt in water

(v) Digestion of food

(vi) Melting of ice

Classify the following as physical or chemical changes:

(i) Formation of curd from milk

(ii) Condensation of steam

(iii) Growth of a plant

(iv) Breaking of a glass tumbler

Separate the following into physical and chemical changes:

Sublimation of a solid, Decomposition of water into hydrogen and oxygen by passing electric current,

Formation of clouds, Making a fruit salad from raw fruits, Dissolving carbon dioxide in water.