Q. If an iodized salt contains 1% KI and a person takes 2 g of the salt every day, the iodide ions going into his body every day would be approximately
A) 7.2$\times 10^{21}$
B) 7.2$\times 10^{19}$
C) 3.6$\times 10^{21}$
D) 9.5$\times 10^{19}$
Explanation
(b)
The mass of KI in 2g salt $= \frac{2 \times 1}{100} = 0.02g$
$= \frac{0.02}{39 + 127}$ mol
$= \frac{0.02}{166} \times 6.02 \times 10^{23}$ ions
$= 7.2 \times 19^{19}$ ions
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.