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3 years ago

Calculate the molality of a 5.73 M ethanol (C2H5OH) solution whose density is 0.9327 g/mL.

Chemistry

1 answer:

Natalka [10]3 years ago

4 0

Answer:

Molality = 8.57 m

Explanation:

Given data:

Molarity of solution = 5.73 M

density = 0.9327 g/mL

Molality of solution = ?

Solution:

Molality = moles of solute / kg of solvent.

Kg of solvent:

Mass of 1 L solution = density× volume

Mass of 1 L solution = 0.9327 g/mL × 1000 mL

Mass of 1 L solution = 932.7 g

Mass of solute:

Mass of 1 L = number of moles × molar mass

Mass = 5.73 mol × 46.068 g/mol

Mass = 263.97 g

Mass of solvent:

Mass of solvent = mass of solution - mass of solute

Mass of solvent = 932.7 g - 263.97 g

Mass of solvent = 668.73 g

In Kg = 668.73 /1000 = 0.6687 Kg

Molality:

Molality = number of moles of solute / mass of solvent in Kg

Molality = 5.73 mol / 0.6687 Kg

Molality = 8.57 m

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Explanation:

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A patient receives 3.3 L of glucose solution intravenously (IV). If 100. mL of the solution

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Answer:

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Explanation:

The question is missing the concentration of the glucose solution. Standard glucose concentration for IV solution is 5% or 5g of glucose every 100mL of solution.

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We are given:

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