Question

Is ${\mathrm{SO}}_3$ an acid or base?

Answer 1

Sulfuric oxide:

1. Sulfur trioxide is an inorganic gas that is an oxide of sulfur and is colorless.
2. It is a chemical that is extremely reactive, a powerful oxidizer, and a fire hazard.
3. Non-metallic oxide is created when non-metals and oxygen react. They are acidic in nature
4. When dissolved in water, they produce an acidic solution that turns the litmus solution red.
5. Sulfur trioxide when reacted with water gives sulfuric acid which is a strong acid
6. .$\underset{\mathrm{Sulfur}\mathrm{trioxide}}{{\mathrm{SO}}_3\left(\mathrm{aq}\right)}+\underset{\mathrm{Water}}{{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}\to \underset{\mathrm{Sulfuric}\mathrm{acid}}{{\mathrm{H}}_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)}$
7. Also, the atomic number of sulfur $=16$ and its electronic configuration is$1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{6}3{\mathrm{s}}^{2}3{\mathrm{p}}^4$. Sulfur can accept two more electrons to complete its octet. Hence, it acts as lewis acid.

Therefore, ${\mathrm{SO}}_3$ is an acid.