Solutions Question 405
Question: Suppose 5 gm of $ CH_3COOH $ is dissolved in one litre of ethanol. Assume that no reaction between them takes place. Calculate molality of resulting solution if density of ethanol is 0.789 gm/ml.
Options:
A) 0.0856
B) 0.0956
C) 0.1056
D) 0.1156
Show Answer
Answer:
Correct Answer: C
Solution:
Weight of $ CH_3COOH $ dissolved = 5 g Eq. of $ CH_3COOH $ dissolved $ =\frac{5}{60} $ Volume of ethanol = 1 litre = 1000 ml.
$ \therefore $ Weight of ethanol =1000 $ \times $ 0.789 = 789 g
$ \therefore $ Molality of solution $ =\frac{Moles,of,solute}{Weight,of,solvent,in} $ $ =\frac{\frac{5}{60\times 789}}{1000}=0.1056 $
