What is the molality of ethanol (C₂H₅OH)in an aqueous solution that is 39.8% ethanol by mass? A) 1 m B) 0 m C) 14 m D) 1 m.. E) 84.0 m

Question

Quizplus · Accepted Answer

Molality (m) is defined as the number of moles of solute per kilogram of solvent.

To find the molality of ethanol in the solution, we need to first calculate the mass of ethanol and water in the solution.

Assuming we have 100 g of the solution,

mass of ethanol = 39.8 g 
mass of water = 100 g - 39.8 g = 60.2 g

Next, we need to convert the mass of ethanol to moles. 
molar mass of ethanol (C2H5OH) = 46.07 g/mol

moles of ethanol = 39.8 g / 46.07 g/mol = 0.864 mol

Finally, we can calculate the molality using the equation:

molality = moles of solute / mass of solvent (in kg)

mass of solvent (in kg) = 60.2 g / 1000 g/kg = 0.0602 kg

molality = 0.864 mol / 0.0602 kg = 14.36 m

Round off to two significant figures to get the answer of 14 m.

What Is the Molality of Ethanol (C2H5OH)in an Aqueous Solution