Question

Which of the following will not have a mass of 10 g?

• A. $0.1\, mol\, CaCO_3$
• B. $1.51 \times 10^{23} Ca^{2+}$ ions
• C. 0.16 mol of $CO_3$ ions
• D. $7.525 \times 10^{22}$ Br atom

Answer 1

Answer: (C)

$0.1$ mole $CaCO_{3}=0.1\times100=10\,g$
$1.51\times10^{23}\, Ca^{2+}$ ions $=\frac{1.51\times10^{23}}{6.023\times10^{23}}\times40$
$0.16$ mol of $CO_{3}^{2-}$ ions $=0.16\times60=9.6\,g$
$7.525\times 10^{22}\,Br$ atoms $=\frac{7.525\times10^{22}}{6.02\times10^{23}}\times80$
$=10\,g$