Question

6. 1 L of a gas is at a pressure of 10 °mm of Hg at 25°C: How many molecules are present in the vessel? a. 3.2 x 10 b. 3.2 x 1013 [2011] C. 3.2 x 1010 d. 3 x 104 JUU liquofiod hoonuse 20091

IIT/JEE

Chemistry

Solution

129

5.0 (2 ratings)

( P=10^{-6} mathrm{mm} ) of ( mathrm{Hg} ) ( V=12 ) ( T=273+25=298 mathrm{k} ) ( P rightarrow quad 760 quad m m ) of ( H g=1 ) atm ( 10^{-6} mathrm{mm} ) of ( mathrm{Hg}=? ) ( x=frac{10^{-6} x 1}{760}=1.316 times 10^{-9} mathrm{at} ) Applying ges lqw ( P V=n R T ) ( 1-316 times 10^{-9} times 1=n times 0.0821 times 298 ) ( n=5.4 times 10^{-11} ) moles mole ( =6.02 times 10^{23} ) molecules ( 5 cdot 4 times 10^{-11}=5 cdot 4 times 6 cdot 02 times 10^{12} ) moles ( 32 cdot 51 times 10^{12} ) molecules ( 3 cdot 25 times 10^{13} ) molecules