Give reasons for the following:
(i) Element carbon forms compounds mainly by covalent bonding.
(ii) Diamond has a high melting point.
(iii) Graphite is a good conductor of electricity.
(iv) Acetylene bums with a sooty flame.
(v) Kerosene does not decolourise bromine water while cooking oils do.
(i) It is because carbon has four valence electrons, it cannot gain or lose four electrons because high energy is needed. It can only share four electrons.
(ii) It is due to strong covalent bonds and compact structure of diamond.
(iii) It is due to presence of free electrons in graphite because each carbon is linked to three more carbon atoms.
(iv) It is due to high percentage of carbon, it burns with sooty or smoky flame.
(v) Kerosene oil is mixture of saturated hydrocarbons therefore does not decolourise bromine water.