Colligative Properties

%5CDelta%20%7B%7B%5CTau%20%7D_%7Bf%7D%7D%3Di%5Ctimes%20%7B%7Bk%7D_%7Bf%7D%7D%5Ctimes%20m

%5Ctext%7BIons%7D%5C%2C%5Ctext%7Bat%7D%5C%2C%5Ctext%7Bequilibrium%7D%5Coverset%7BHBr%7D%7B%5Cmathop%7B1-%5Calpha%20%7D%7D%5C%2C%5Cxrightarrow%7B%7B%7D%7D%5Cunderset%7B%5Calpha%20%7D%7B%5Cmathop%7B%7B%7BH%7D%5E%7B%2B%7D%7D%7D%7D%5C%2C%2B%5Cunderset%7B%5Calpha%20%7D%7B%5Cmathop%7BB%7B%7Br%7D%5E%7B-%7D%7D%7D%7D%5C%2C

%5Ctherefore

%5Ctext%7BTotal%7D%5C%2C%5Ctext%7Bions%7D%3D1-%5Calpha%20%2B%5Calpha%20%2B%5Calpha

%3D1%2B%5Calpha

%5Ctherefore

i%3D1%2B%5Calpha

Given,

%7B%7Bk%7D_%7Bf%7D%7D%3D1.86%5C%2C%5Ctext%7BK%7D%5C%2C%5Ctext%7Bmo%7D%7B%7B%5Ctext%7Bl%7D%7D%5E%7B-1%7D%7D

mass of

%5Ctext%7B%20%7D%5C!%5C!~%5C!%5C!%5Ctext%7B%20HBr%20%3D%7D%5C%2C%5Ctext%7B8%7D%5Ctext%7B.1%20g%7D

mass of

%5Ctext%7B%20%7D%5C!%5C!~%5C!%5C!%5Ctext%7B%20%7D%7B%7B%5Ctext%7BH%7D%7D_%7B%5Ctext%7B2%7D%7D%7D%5Ctext%7BO%7D%5C%2C%5Ctext%7B%3D100%20g%7D

%5Ctext%7B(%20%7D%5C!%5C!%5Calpha%5C!%5C!%5Ctext%7B%20)%7D%5C%2C%5C%2C%5Ctext%7B%3D%7D

degree of ionization

%3D90%25

m

(molality)

%5Ctext%7B%3D%20%7D%5Cfrac%7B%5Ctext%7Bmass%7D%5C%2C%5Ctext%7Bof%7D%5C%2C%5Ctext%7Bsolute%2Fmol%7D%5Ctext%7B.wt%7D%5Ctext%7B.of%7D%5C%2C%5Ctext%7Bsolute%7D%7D%7B%5Ctext%7Bmass%20of%20solventin%20kg%7D%7D

%3D%5Cfrac%7B8.1%2F81%7D%7B100%2F1000%7D

i%3D1%2B%5Calpha

%3D1%2B90%2F100

%3D1.9

%5CDelta%20%7B%7BT%7D_%7Bf%7D%7D%3Di%5Ctimes%20%7B%7Bk%7D_%7Bf%7D%7D%5Ctimes%20m

%3D1.9%5Ctimes%201.86%5Ctimes%20%5Cfrac%7B8.1%2F81%7D%7B100%2F1000%7D

%3D3.534%7B%7B%5C%2C%7D%5E%7Bo%7D%7DC

%5CDelta%20%7B%7BT%7D_%7Bf%7D%7D%3D

(depression in freezing point) = freezing point of water - freezing point of solution 3.534 = 0-freezing point of solution

%5Ctherefore

Freezing point of solution

%3D-3.534%7B%7B%5C%2C%7D%5E%7Bo%7D%7DC

Chapter Questions
2 MCQs