Answer:
The molality of the solution is 1.57 molal
Explanation:
Step 1: Data given
Mass of benzoic acid = 64.7 grams
Volume of ethanol = 427.1 mL
Density of ethanol = 0.789 g/mL
Molar mass benzoic acid = 122.12 g/mol
Step 2: Calculate moles benzoic acid
Moles benzoic acid = mass benzoic acid / molar mass benzoic acid
Moles benzoic acid = 64.7 grams / 122.12 g/mol
Moles benzoic acid = 0.530 moles
Step 3: Calculate mass ethanol
Mass ethanol = density * volume
Mass ethanol = 0.789 g/mL * 427.1 mL
Mass ethanol = 336.98 grams = 0.33698 kg
Step 4: Calculate molality
Molality = moles benzoic acid / mass ethanol
Molality = 0.530 moles / 0.33698 kg
Molality = 1.57 molal
The molality of the solution is 1.57 molal
