Question
Chemistry Question on Colligative Properties
The boiling point of water (100∘C) becomes 100.52∘C, if 3 grams of a non-volatile solute is dissolved in 200ml of water. The moleular weight of solute is (if Kb for water is =0.6K/m )
A
17.3g.mol−1 :
B
15.4g.mol−1 :
C
12.2g.mol−1 :
D
20.4g.mol−1 :
Answer
17.3g.mol−1 :
Explanation
Solution
As deration in boilding point is given by: ΔT=Kb× molality Putting the various values, we get: 100.52−100.00=0.6×200/10003/M ⇒M=17.3gmol−1