Which of the following exists as covalent crystals in the solid state? (1) Silicon (2) Sulphur (3) Phosphorous (4) Iodine

Dear student,

 

Silicon exists as a covalent crystal because it has a tetravalency and thus its ionic forms are non existent as for them to be stable Si would have to either gain or lose 4 electrons in the outermost shell which requires either gain or loss of large amount of energy thus it only forms covalent bonds with other compounds and its behaviour is very much similar to Carbon which is also covalent in nature.

 

Hope it helps.

Thanks and regrads,

Kushagra