1.Q. Why carbon form covalent bond by sharing electron? Ans: Carbon has four electrons in its outermost shell and needs to gain or lose four electrons to attain noble gas configuration. (i) it could gain four electrons forming C 4- anion. But it would be difficult for the nucleus with six protons to hold on to ten electrons, that is, four extra electrons. (ii) It could lose four electrons forming C 4+ cation. But it would require a large amount of energy to remove four electrons leaving behind a carbon cation with six protons in its nucleus holding on to just two electrons. Hence, it is difficult for the carbon to lose or gain four electrons therefore carbon formcovalent bond by sharing electron 2.Q. Why do covalent compounds are in gaseous or liquid state at normal temperature and pressure. Ans: due to Weak Vanderwaal’s forces present between the molecules of covalent compounds. 3.Q. Why do covalent compounds have less melting and boiling points? Ans: As ene
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