Question

Is H₂S a weak dibasic acid?

Answer 1

H₂S is a weak dibasic acid, The term "base" refers to a substance that can take protons, whereas the term "acid" refers to a molecule that can donate protons.

1. A base's ability to take protons is known as its basicity, and an acid's ability to donate protons is known as its acidity.
2. The ability of an acid to neutralize the base is referred to as the basicity of an acid.
3. To neutralize the base, an acid must donate a certain number of protons, which determines how basic the acid is.
4. The ability of a base to neutralize acid is known as the acidity of the base.
5. The acidity of a base is determined by the number of protons it accepts to neutralize an acid
6. Two hydrogen atoms can be added to hydrogen sulfide to neutralize bases.
7. Therefore, the two base molecules will be neutralized by hydrogen sulfide. Hydrogen sulfide is a dibasic acid because it can donate two protons to neutralize two base molecules.${\text{H}}_{\text{2}}\text{S}\to \text{H}{\text{S}}^{-}+{\text{H}}^{\text{+}}{\text{K}}_{\text{1a}}=1.0\times {10}^{-7}$
   $\text{H}{\text{S}}^{-}\to {\text{S}}^{2-}+{\text{H}}^{\text{+}}{\text{K}}_{\text{2a}}=1.3\times {10}^{-14}$
8. The acid dissociation constant hydrogen sulfide is very less is weak acid, so it is a weak diabasic acid.

Diagram:

Hence, ${\mathbf{H}}_{\mathbf{2}}\mathbf{S}$ is a weak dibasic acid.