If 10 grams of NaCl is dissolved in 500 mL of water, what is the molality of the

If 10 grams of NaCl is dissolved in 500 mL of water, what is the molality of the solution? (Molar mass of NaCl = 58.5 g/mol)

If 10 grams of NaCl is dissolved in 500 mL of water, what is the molality of the solution? (Molar mass of NaCl = 58.5 g/mol)

Step 1: Identify the mass of NaCl (the solute) which is given as 10 grams.
Step 2: Identify the molar mass of NaCl, which is given as 58.5 g/mol.
Step 3: Calculate the number of moles of NaCl using the formula: moles = mass (g) / molar mass (g/mol). So, moles of NaCl = 10 g / 58.5 g/mol.
Step 4: Perform the calculation: 10 g / 58.5 g/mol = 0.171 moles of NaCl.
Step 5: Identify the volume of water (the solvent) which is given as 500 mL. Convert this to kilograms: 500 mL of water = 0.5 kg (since 1 L of water = 1 kg).
Step 6: Use the formula for molality: molality (m) = moles of solute / kg of solvent. Substitute the values: molality = 0.171 moles / 0.5 kg.
Step 7: Perform the calculation: 0.171 moles / 0.5 kg = 0.342 m.

Molality Calculation – Understanding how to calculate molality using moles of solute and mass of solvent.
Molar Mass – Using the correct molar mass to convert grams of solute to moles.
Units of Measurement – Recognizing the importance of using kg for solvent mass in molality calculations.