Question

state the reason why carbon can neither form c4- anions and c4+ cations. but forms covalent compounds. also state reason to explain why covalent compounds are bad conductor of electricity and have low melting and boiling point?

Answer 1

$hey \: friend$!

The atomic number of carbon is 6 which means that a neutral atom of carbon contains 6 electrons .So it is clear that carbon has 4 electrons in the outermost shell of its atom .
Since a carbon has 4 electrons in its outermost shell ,so it should either lose 4 electrons or gain 4 electrons to achieve the inert gas electron configuration and become stable.
Now,carbon atom is very small due to which its outermost electrons are strongly held by the nucleus.Si,it is no possible to remove 4 electrons from a carbon atom to give it the inert gas electron arrangement.It is also not possible to add as many as 4 electrons to a carbon atom due to energy considerations, a nd acquire the inert gas configuration .Since carbon atom can achieve the inert gas electron arrangement only by the sharing of electrons ,therefore ,carbon always form covalent bonds .
The covalent bonds between the various carbon atom is very strong and do not break easily .This is the reason for or formation of strong bonds by the carbon atom is their small size This makes the carbon compounds exceptionally stable.No other element exhibits the property of catenation to the extent seen in carbon compounds .
The covalent compound are bad conductor of electricity because the electrons shared between their atoms have no charged particles.
The covalent compounds have low melting points because the carbon is "Tetravalent".However its molecules are joined by relatively weak force.So covalent compounds have low melting and boiling point .
$hope \: it \: heps \: you$!

Answer 2

♤ Carbon can't lose 4 electron to form C^4+ ions as very high energy is required to remove 4 electrons.

♤ Carbon can not gain 4 electron to form C^4- ions as 6 protons can not hold 10 ♤ electrons and Energy needs to be supplied to overcome repulsion.

♤ Carbon can share 4 electron to form covalent compounds.

♤ Carbons do not conduct electricity as they are non - polar and do not form ions.

♤ They have low melting points and boiling points due to weak van der Waal's force of attraction between molecules