The formula of the sulphate of an element M is M₂(SO₄)₃. Write the formula of its

(a) Chloride

(b) Oxide

(c) Phosphate

(d) Acetate

Given, formula of sulphate is M₂(SO₄)₃.

$\text{M}$2(\text{SO}4)3 = \underset{\phantom{2}{2}}{\text{M}} \space {\nearrow}\mathllap{\nwarrow} \space \underset{3}{\text{SO}4} \Rightarrow \overset{\phantom{3}{3}}{\text{M}} \space {\nearrow}\mathllap{\nwarrow} \space \overset{2}{\text{SO}_4} \\[0.5em]

∴ Valency of M is 3.

(a) Formula of Chloride:

$\text{M}^{3+} \space \text{Cl}^{1-} \\[1em] \overset{\phantom{3}{3}}{\text{M}} \space {\swarrow}\mathllap{\searrow} \space \overset{1}{\text{Cl}} \Rightarrow \underset{\phantom{1}{1}}{\text{M}} \space {\swarrow}\mathllap{\searrow} \underset{\phantom{3}{3}}{\text{Cl}} \\[1em] \text{M}\text{Cl}_3$

∴ Formula of chloride of element M is MCl₃

(b) Formula of Oxide:

$\text{M}^{3+} \space \text{O}^{2-} \\[1em] \overset{\phantom{3}{3}}{\text{M}} \space {\swarrow}\mathllap{\searrow} \space \overset{2}{\text{O}} \Rightarrow \underset{\phantom{2}{2}}{\text{M}} \space {\swarrow}\mathllap{\searrow} \underset{\phantom{3}{3}}{\text{O}} \\[1em] \text{M}$2\text{O}3

∴ Formula of oxide of element M is M₂O₃

(c) Formula of Phosphate:

$\text{M}^{3+} \space \text{PO}$4^{3-} \\[1em] \text{Dividing by H.C.F. it becomes} \\[1em] \text{M}^{1+} \space \text{PO}4^{1-} \\[1em] \overset{\phantom{3}{1}}{\text{M}} \space {\swarrow}\mathllap{\searrow} \space \overset{1}{\text{PO}4} \Rightarrow \underset{\phantom{2}{1}}{\text{M}} \space {\swarrow}\mathllap{\searrow} \underset{\phantom{3}{1}}{\text{PO}4} \\[1em] \text{MPO}_4

∴ Formula of phosphate of element M is MPO₄

(d) Formula of Acetate:

$\text{M}^{3+} \space \text{CH}$3\text{COO}^{1-} \\[1em] \overset{\phantom{3}{3}}{\text{M}} \space {\swarrow}\mathllap{\searrow} \space \overset{\phantom{CHCOOO}1}{\text{CH}3\text{COO}} \Rightarrow \underset{\phantom{1}{1}}{\text{M}} \space {\swarrow}\mathllap{\searrow} \underset{\phantom{3}{3}}{\text{CH}3\text{COO}} \\[1em] \text{M}\text{(CH}3\text{COO})_3

∴ Formula of acetate of element M is M(CH₃COO)₃