Q. Ions of an element are chemically inactive because of the octet configuration of their valence shells .then how do this reaction takes place?
(i) $M{n}^{2+}\left(aq\right)+H_{2}S\left(g\right) \to MnS+H^{+}\left(aq\right)$

Dear Student

The element having a complete octet gives its electrons to another element to form ionic bond. Example- Zn gives loan pair to sulfur and make Zn⁺²S^-2=ZnS. The same concept is applied in the case of MnS.

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