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What is the molality of a solution that contains 5 moles of solute in 100 kilograms of water?

2 Answers

4 votes
Answer:
molality = (moles of solute) / (kilogram of solvent)

moles of solute = (75.2 g AgClO4) / (mole mass AgClO4)
moles of solute = (75.2 g AgClO4) / (207.3206 g/mol)
moles of solute = 0.3627232 mol

molality = (0.3627232 mol) / (0.0752 Kg)
molality = 4.8234468 m or 4.82 m rounded to three significant figures
User Yeasin Abedin
by
8.4k points
7 votes

Answer:


m=0.05m

Step-by-step explanation:

Hello,

In this case, molality is defined as:


m=(n_(solute))/(m_(solvent))

Whereas the mass of the solvent is given in kilograms. In such a way, for 5 moles of solute and 100 kg of water, the molality turns out:


m=(5mol)/(100kg)\\ m=0.05(mol)/(kg)

Now it is important to notice that the molal units (m) equals mol/kg, thereby:


m=0.05m

Best regards.

User Hugo Tunius
by
6.9k points