Question

Which among the following compound possess trivalent cation and divalent negative radical?

• A. Calcium sulphide
• B. Aluminum nitrate
• C. Aluminum chromate
• D. Cupric hydroxide

Answer 1

The correct option is C

Aluminum chromate

Explanation for the correct option (C):

• A cation is an ion carrying a positive charge. Cations are formed by losing electrons due to which they develop a positive charge.
• Trivalent Cations are the positively charged ions having their valency (3+). It means divalent ions are formed by losing three valence electrons and attaining a positive charge.
• A radical is an atom or group of an atom of the same or different elements that behave in the manner of positive or negative ions and elements [or radicals] with valency 2 valency are called divalent negative radicals.
• Aluminum chromate ${\mathrm{Al}}_2{\left(\mathrm{CrO}4\right)}_3$ has trivalent cation and Chromate ${{\mathrm{CrO}}_4}^{2-}$as a divalent negative radical.

Explanation for the incorrect option:

(A) Calcium sulfide ($CaS$) has divalent cation i.e., $\left({\mathrm{Ca}}^{2+}\right)$ and Sulphide $\left({\mathrm{S}}^{2-}\right)$ has divalent negative radical.

(B) As Aluminum nitrate $\mathrm{Al}{\left({\mathrm{NO}}_3\right)}_3$is formed by the trivalent cation Aluminum $\left({\mathrm{Al}}^{3+}\right)$ and monovalent negative Nitrate $\left({{\mathrm{NO}}_3}^{-}\right)$ (anion).

(D) Cupric hydroxide $\mathrm{Cu}{\left(\mathrm{OH}\right)}_2$ has divalent cation i.e., $\left({\mathrm{Cu}}^{2+}\right)$ and Hydroxide $\left({\mathrm{OH}}^{-}\right)$ is a monovalent negative radical.

Thus, option (C) i.e., Aluminum chromate ${\mathrm{Al}}_2{\left(\mathrm{CrO}4\right)}_3$is the correct one.