I will use [pV/T] in the state 1 = [pV/T] in the state 2.
State 1:
p = 1.0 atm
V = 25 liter
T = 100 + 273.15 = 373.15 K
State 2:
p = 19.71 mmHg * 1.atm / 760 mmHg = 0.0259atm
V= ?
T = 25 + 273.15 = 298.15 K
Application of the formula
1.0 atm * 25 liter / 373.15 k = 0.0259 atm * V / 298.15 K =>
V = [1.0atm * 25 liter / 373.15 K]*298.15K/0.0259atm = 771 liter
Difference in density between the two liquids
The gas flows from higher concentration/pressure to lower concentration/pressure, which is outside the ball.
If your options are among the following:
<span>0.64 M 1.0 M 0.32 M 0.16 M.
Then the correct answer is 0.64 M. I hope this is what you were looking for</span>