  # Calculate the Molarity of a solution of ethanol in water in which the mole fraction of ethanol is 0.040 (assume the density of water to be one).

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Updated on: September 25th, 2023 The molarity of a solution of ethanol in water in which the mole fraction of ethanol is 0.040 is 2.1M

Now we have to calculate the molarity

The number of moles of solute per litre of solution is known as the molarity (M) of a solution.

Molarity = no. of moles of solute/ litres of solution

Step 1: Now we have determine the number of moles of ethanol and water

Moles of Water = 1 – 0.04

Moles of Ethanol = 0.04 Mol

Moles of Water = 0.96Mol

Step 2: Now we have to determine the mass of ethanol and water

Number of moles = Given mass/ Molar mass

Mass = number of moles x molar mass

Mass of water = 0.96 x 18

Mass of water = 17.3 g

Mass of ethanol = 0.04 x 46

Mass of ethanol = 1.84 g

Step 3: Now we have to determine the total mass of soluion

Total mass of the solution = 17.3 + 1.84

Total mass of the solution = 19.1 g

Step 4: Now we have to determine the volume

Density = 1g/mL (Assumed)

Density = mass/ volume

On rearranging we get

Volume = mass/ density

Volume = 19.1/1

Volume = 19.1 mL

Volume = 0.0191 L

Determination of Molarity

Molarity = 0.04/0.0191

Molarity = 2.1 M

Consequently, a solution of ethanol in water has a molarity of 2.1M.

Summary:-

## Calculate the Molarity of a solution of ethanol in water in which the mole fraction of ethanol is 0.040 (assume the density of water to be one).

A solution of ethanol in water with a mole fraction of 0.040 has a molarity of 2.1M. Ethanol is a plant fermentation by-product which is natural and it can also be produced through the hydration of ethylene.

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