Calculate osmotic pressure of CaCl 2 solution at 36ºC, if its molarity is 0.02
mol/L, degree of dissociation is 68 %.
Answers
Answer:
Explanation:
According to Van't Hoff's equation, the osmotic pressure
Π=iCRT=
V
in
B
RT
.
Here, i is the Van't Hoff's factor, C is the molar concentration, R is the ideal gas constant, T is temperature, nB is the number of moles of calcium chloride and V is the volume of the solution.
Now we have given below values:
π = 0.75 atm
V = 2.5L
i = 2.47
T = (27+273) K = 300K
and R = 0.0821L atm k
−1
mol
−1
0.75=
2.5
2.47×n
B
×0.0821×300
n
B
=0.0308 mol
The molar mass of calcium chloride is 111 g/mol.
Amount of calcium chloride dissolved =0.0308×111=3.42 g.
According to Van't Hoff's equation, the osmotic pressure
Π=iCRT=
V
in
B
RT
.
Here, i is the Van't Hoff's factor, C is the molar concentration, R is the ideal gas constant, T is temperature, nB is the number of moles of calcium chloride and V is the volume of the solution.
Now we have given below values:
π = 0.75 atm
V = 2.5L
i = 2.47
T = (27+273) K = 300K
and R = 0.0821L atm k
−1
mol
−1
0.75=
2.5
2.47×n
B
×0.0821×300
n
B
=0.0308 mol
The molar mass of calcium chloride is 111 g/mol.
Amount of calcium chloride dissolved =0.0308×111=3.42 g.