Answer:
mass % = 28.4%
mole fraction = 0.252
molality = 3.08 molal
molarity = 2.69 M
Explanation:
Step 1: Data given
Volume of toluene = 50.0 mL = 0.05 L
Density toluene = 0.867 g/mL
Molar mass toluene = 92.14 g/mol
Volume of benzene = 125 mL = 0.125 L
Density benzene = 0.874 g/mL
Molar mass benzene = 78.11 g/mol
Step 2: Calculate masses
Mass = density * volume
Mass toluene = 50.0 mL * 0.867 g/mL = 43.35 g
Mass benzene = 125 mL * 0.874 g/mL = 109.25 g
Step 3: Calculate number of moles
Moles = mass / molar mass
Moles toluene = 43.35 grams /92.14 g/mol = 0.470
5 moles
Moles benzene = 109.25 grams / 78.11 g/mol = 1.399 moles
Step 4: Calculate molarity of toluene
Molarity = moles / volume
Molarity toluene = 0.4705 moles / 0.175 L = 2.69 M
Step 5: Calculate mass % of toluene
Mass % = (43.35 grams / (43.35 + 109.25) )*100 % = 28.4 %
Step 6: Calculate mole fraction of toluene
Mole fraction toluene = Moles toluene / total number of moles
Mole fraction toluene = 0.4705 / (0.4705 + 1.399) = 0.252
Step 7: Molality of toluene
Molality = number of moles / mass
Molality of toluene = 0.4705 moles / (0.04335 + 0.10925)
Molality of toluene = 3.08 molal