Question

$0.1gCaC{O}_3$ will contain:

• A. $0.1N_{A}C{a}^{2-}ion$
• B. $0.01N_{A}C{a}^{2+}ion$
• C. $0.001N_{A}C{a}^{2+}ion$
• D. $N_{A}C{a}^{2+}ion$

Answer 1

The correct option is C $0.001N_{A}C{a}^{2+}ion$

$CaC{O}_3⟶C{a}^{2+}+C{O}_3^{2-}$

$n$ mole of $CaC{O}_3$ will give $n$ mole of $C{a}^{2+}$ ion.

So Mole of $CaC{O}_3$ = Mole of $C{a}^{2+}$

$\Rightarrow \frac{Givenmass}{Molarmass}=$ Moles of $C{a}^{2+}$

$\Rightarrow \frac{.1}{100}=$ Mole of $C{a}^{2+}$

$\therefore$ Moles of $C{a}^{2+}=0.001mole$

Number of ions = $N_A\times moles$

Number of ions = $N_A\times .001$

Hence, option $C$ is correct.