Give some examples of the Tyndall effect observed in your surroundings.

Which of the tubes in Fig. $(a)$ and $(b)$ will be more effective as a condenser in the distillation apparatus?

State whether the following statement is true or false:
During the burning of a candle,only a chemical change takes place.

Elements are classified as metals,non-metals,and metalloids. Give any one property of each. Also,give one example of each.

Two substances,$A$ and $B$,were made to react to form a third substance,$A_2B$,according to the following reaction: $2A + B \to A_2B$. Which of the following statements concerning this reaction are incorrect?
$(i)$ The product $A_2B$ shows the properties of substances $A$ and $B$.
$(ii)$ The product will always have a fixed composition.
$(iii)$ The product so formed cannot be classified as a compound.
$(iv)$ The product so formed is an element.

Compare physical and chemical changes.