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


40
1