Question

At constant P of 0.0821 atm log V vs log T graph is plotted for 3 samples of ideal gas as shown. Value of moles of gas in these three samples is respectively:

• A. $3,1, \frac{1}{2}$
• B. $\frac{1}{2}, 1,3$
• C. $1, \frac{1}{2}, 3$
• D. $\frac{1}{2}, 3,1$

Answer 1

Answer: (A)

$\frac{ V }{ T }=$ constant $( K )$

$\log V =\log T +\log K$ where $K =\frac{ nR }{ P }$

For 2 graph

$\log \frac{ nR }{ P }=0=\log 1 $

$\frac{ nR }{ P }=1( R = P ) \text { or } n =1 mol$

for 1 graph

$\log \frac{ nR }{ P }=\log 3 \text { or } n =3 mol$

for 3 graph

$\log \frac{ nR }{ P } =-\log 2=\log \frac{1}{2} $

$n =\frac{1}{2} mol$