What are metalloids? Give examples.

Fill in the blanks:
$(a)$ $A$ colloid is a .......... mixture and its components can be separated by the technique known as .........
$(b)$ Ice,water,and water vapour look different and display different ......... properties but they are ......... the same.
$(c)$ $A$ mixture of chloroform and water taken in a separating funnel is mixed and left undisturbed for some time. The upper layer in the separating funnel will be of ......... and the lower layer will be that of .........
$(d)$ $A$ mixture of two or more miscible liquids,for which the difference in the boiling points is less than $25 \, K$,can be separated by the process called .........
$(e)$ When light is passed through water containing a few drops of milk,it shows a bluish tinge. This is due to the ......... of light by milk and the phenomenon is called ......... . This indicates that milk is a ......... solution.

$(a)$ Tabulate the differences between a suspension and a true solution with respect to $(i)$ filtration,$(ii)$ transparency,and $(iii)$ stability.
$(b)$ Give two examples from daily life where the Tyndall effect is observed.

$A$ solution contains $50 \, g$ of sugar in $350 \, g$ of water. Calculate the concentration of the solution in terms of mass by mass percentage of the solution. (in $\%$)

The teacher instructed three students $A$,$B$ and $C$ respectively to prepare a $50\%$ (mass by volume) solution of sodium hydroxide $(NaOH)$. $A$ dissolved $50\,g$ of $NaOH$ in $100\,mL$ of water,$B$ dissolved $50\,g$ of $NaOH$ in $100\,g$ of water while $C$ dissolved $50\,g$ of $NaOH$ in water to make $100\,mL$ of solution. Which one of them has made the desired solution and why?

Why does a mixture not have a fixed melting or a fixed boiling point?