Write a note on the covalent character of elements in period two. Give examples to illustrate this phenomenon.

Question

Quizplus · Accepted Answer

The Answer is Because of the smaller atomic size, simple binary ionic compounds of second-period elements have more covalent character than the corresponding compounds formed from their heavier congeners. The very small cations derived from second-period elements have a high charge-to-radius ratio and can therefore polarize the filled valence shell of an anion. As such, the bonding in such compounds has a significant covalent component, giving the compounds properties that can differ significantly from those expected for simple ionic compounds. As an example, LiCl, which is partially covalent in character, is much more soluble than NaCl in solvents with a relatively low dielectric constant, such as ethanol (ε = 25.3 versus 80.1 for H₂O).

Write a Note on the Covalent Character of Elements in Period