To avoid the precipitation of hydroxides of $\mathrm{Ni}^{2+}, \mathrm{Co}^{2+}, \mathrm{Zn}^{2+}$ a

Question

To avoid the precipitation of hydroxides of $\mathrm{Ni}^{2+}, \mathrm{Co}^{2+}, \mathrm{Zn}^{2+}$ and $\mathrm{Mn}^{2+}$ along with those of $\mathrm{Fe}^{3+}, \mathrm{Al}^{3+}$ and $\mathrm{Cr}^{3+}$ the third group solution should be:

Professor PC Thomas Classes · Answer

See detailed solution for explanation.