Determine the amount of CaCl2 (i = 2.47) dissolved in 2.5 litre of water such that its osmotic pressure is 0.75 atm at 27° C.
Given-
Vant Hoff’s factor, i = 2.47
osmotic pressure, 
= 0.75 atm
Volume of solution = 2.5L.
To determine the amount of CaCl2, we use vant Hoff’s equation for dilute
solutions, given as,
where, n is the number of moles of solute, R is solution constant which is equal
to the gas constant and T is the absolute temperature.
where, the molecular mass of CaCl2 is 111, t = 300 K (270C + 273 K) and R = 0.082,
Hence, the amount of CaCl2 dissolved is 3.425g
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