Question

Calculate the molality of a solution containing 100.7 g of glycine (NH2CH2COOH) dissolved in 3.466 kg of H2O.

Answer 1

Answer : The molality of a solution is, 0.387 mol/kg

Explanation : Given,

Mass of solute (glycine) = 100.7 g

Mass of solvent (water) = 3.466 kg

Molar mass of glycine = 75.1 g/mole

Formula used :

$Molality=\frac{\text{Mass of solute}}{\text{Molar mass of solute}\times \text{Mass of solvent}}$

Now put all the given values in this formula, we get:

$Molality=\frac{100.7g}{75.1g/mol\times 3.466kg}$

$Molality=0.387mol/kg$

Thus, the molality of a solution is, 0.387 mol/kg

Answer 2

Answer:

The molality of the solution is 0.387 molal

Explanation:

Step 1: Data given

Mass of glycine = 100.7 grams

Mass of H2O = 3.466 kg

Molar mass of glycine = 75.07 g/mol

Step 2: Calculate moles glycine

Moles glycine = mass glycine / molar mass glycine

Moles glycine = 100.7 grams / 75.07 g/mol

Moles glycine = 1.341 moles

Step 3: Calculate molality of the solution

Molality = moles glycine / mass H2O

Molality = 1.341 moles / 3.466 kg

Molality = 0.387 molal

The molality of the solution is 0.387 molal