Q. Number of molecules in 100 mL of each of $O_{2}$, $NH_{3}$ and $CO_{2}$ at STP are in the order
A) $CO_{2} < O_{2} < NH_{3}$
B) $NH_{3} < O_{2} < CO_{2}$
C) $NH_{3} = CO_{2} < O_{2}$
D) All have same number of molecules
Explanation
(d)
100 ML $O_{2},NH_{3}$ and $CO_{2} = \frac{0.1}{22.4} = \frac{1}{224}$ mol
For $O_{2}$no. of molecules $= \frac{1}{224} \times 6.023 \times 10^{23}$
For $NH_{3}$ no. of molecules $= \frac{1}{224} \times 6.023 \times 10^{23}$
For $CO_{2}$ no. of molecules $= \frac{1}{224} \times 6.023 \times 10^{23}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.