Question

What is the molality of c2h5oh in water solution which will freeze at -10c?

Answer 1

you forgot to write Kf value of water.
Here, you should add Kf of water = 1.86

We know,
Depression in freezing pont = depression Constant × molality
e.g., ∆T = Kf × m
Here, ∆T = 10°C [ we neglected sign ]
Kf = 1.86
Now, 10 = 1.86 × m
m = 10/1.86 = 5.37

Hence , molality = 5.3 m

Answer 2

Explanation:

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