Some Basic Concepts Of Chemistry Question 203
Question: Volume of a gas at STP is $ 1.12\times {10^{-7}} $ cc. Calculate the number of molecules in it [BHU 1997]
Options:
A) $ 3.01\times 10^{20} $
B) $ 3.01\times 10^{12} $
C) $ 3.01\times 10^{23} $
D) $ 3.01\times 10^{24} $
Show Answer
Answer:
Correct Answer: B
Solution:
$ \because $ 22400cc of gas at STP has $ 6\times 10^{23} $ molecules
$ \therefore $ 1.12 $ \times {10^{-7}} $ of gas at STP has $ \frac{6\times 10^{23}\times 1.12\times {10^{-7}}}{22400} $ $ =.03\times 10^{14}=3\times 10^{12} $ .