State whether the following statement is true or false:
Metals are malleable,ductile,sonorous,and lustrous.

Which of the following are not compounds?
$(a)$ Chlorine gas
$(b)$ Potassium chloride
$(c)$ Iron
$(d)$ Iron sulphide
$(e)$ Aluminium
$(f)$ Iodine
$(g)$ Carbon
$(h)$ Carbon monoxide
$(i)$ Sulphur powder

Crystallisation is a better technique than simple evaporation. Give one reason to justify the statement.

$A$ mixture of sulphur and carbon disulphide is

Write the role of the following in a water purification system:
$(a)$ Sedimentation tank
$(b)$ Loading tank
$(c)$ Chlorination tank

What happens when a saturated solution is cooled?