Question

Write Lewis dot structure for the following compounds: S, S^2-, Al, Al³⁺

Answer 1

(a) S and S^2-: Atomic number of sulphur is 16 and electronic configuration is [Ne] 3s² 3p⁴, i.e., it has 6 electrons in its valence shell. The Lewis dot symbol of sulphur (S) is

For S^2-, di-negative anion is formed by addition of two electrons. Now, the electronic configuration will be [Ne] 3s² 3p⁶, Hence, the Lewis dot symbol of S^2- is

(b) Al and Al³⁺: Atomic number of aluminium is 13. Its electronic configuration will be [Ne] 3s²3p¹ i.e., the valence electron is 3. The Lewis dot symbol of aluminium (Al) is

The tri-positive ion of aluminium is formed by loss of 3 electrons. Thus, it has three less electrons than aluminium. Its possible electronic configuration will be [Ne]. Hence, the Lewis dot symbol is [Al]³⁺.