(a) Magnesium is used in fireworks because it bums with a dazzling light.
(b) Aluminium is used in making aircraft because it is light and strong. It is mixed with other metals to make it stronger.
(c) Graphite turns paper ***** that is why it is used in the leads of pencils.
(d) Impure diamond is used to cut glass because it is the hardest substance and can easily exert force required for cutting.
