Answer:
The molality of toluene is 7.748 molal
Explanation:
Step 1: Data given
Mass of toluene = 199.7 grams
Mass of benzene = 80.0 gram
Molar mass of benzene = 78.11 g/mol
Molar mass of toluene = 92.14 g/mol
Step 2: Calculate total mass
Total mass = mass of toluene + total benzene
Total mass = 199.7 grams + 80.0 grams
Total mass = 279.7 grams = 0.2797 kg
Step 3: Calculate moles of toluene
Moles toluene = mass toluene / molar mass toluene
Moles toluene = 199.7 grams / 92.14 g/mol
Moles toluene = 2.167 moles
Step 4: Calculate molality of toluene
Molality toluene = moles / mass solution
Molality = 2.167 moles / 0.2797 kg
Molality = 7.748 molal
The molality of toluene is 7.748 molal