Question

Which of the following represents a correct chemical formula? Name it.

• A. $\mathrm{CaCl}$
• B. ${\mathrm{BiPO}}_4$
• C. ${\mathrm{NaSO}}_4$
• D. $\mathrm{NaS}$

Answer 1

The correct option is B

${\mathrm{BiPO}}_4$

Explanation for the correct options:

(B) ${\mathrm{BiPO}}_4$

• ${\mathrm{BiPO}}_4$ represent the correct formula.
• Valency of $\mathrm{Bi}$ is 3 and $\left({\mathrm{PO}}_4\right)$ is 3.
• Its name is Bismuth phosphate.
• Both ions are trivalent.

Explanation for the incorrect options:

(A)$\mathrm{CaCl}$

• $\mathrm{CaCl}$ is not a correct chemical formula.
• Valency of $\mathrm{Ca}$ is $2$ and $\mathrm{Cl}$ is 1 so its correct formula is ${\mathrm{CaCl}}_2$.

(C)${\mathrm{NaSO}}_4$

• ${\mathrm{NaSO}}_4$ is not a correct chemical formula.
• Valency of $\mathrm{Na}$ is 1 and sulfate is 2, hence its correct formula is ${\mathrm{Na}}_2{\mathrm{SO}}_4$.

(D)$\mathrm{NaS}$

• $\mathrm{NaS}$ is not the correct chemical formula.
• Valency of $\mathrm{Na}$ is 1 and $\mathrm{S}$ is $2$, so its correct formula is ${\mathrm{Na}}_2\mathrm{S}$.

Hence, option (B) is correct., ${\mathrm{BiPO}}_4$ is the correct chemical formula.