Osmosis is a process by which the molecules of a solvent pass from a
solution of low solute concentration to a solution of high solute
concentration through a semi-permeable membrane. Osmotic pressure is
a colligative property. When the applied pressure on a solution exceeds its
osmotic pressure, reverse osmosis occurs. When two solutions are
separated by a semipermeable membrane and they have same osmotic
pressure they are said to be isotonic. Of the two solutions separated by a
semipermeable membrane, if one is a lower osmotic pressure, it is said to
be hypotonic relative to the second solution. If it has a higher osmotic
pressure, than the second solution, it is said to be hypertonic relative to
the second solution. The osmotic pressure associated with the fluid inside
the blood cell is equivalent to that of 0.9
solution called normal saline solution and it is safe to inject intravenously.
Osmotic pressure is vital in daily life and nature. It helps in explain, why
IV fluids match blood’s osmotic pressure, its also the principle behind food
preservation using salt or sugar.
Calculate the amount of $CaCl_2$ ($i = 2.59$) dissolved in 2.46 litre of water such that its osmotic pressure is 0.70 atm at $27^\circ C$.
$[$Given: $R = 0.082~L~atm~K^{-1}mol^{-1}$, molar mass of $CaCl_2 = 111~g~mol^{-1}]$
