A solution is made by mixing 25.0 mL of toluene C6H5CH3d=0867gmL with 135.0 mL of benzene C6H6d=0874gmL. Assuming that the volumes add upon mixing, the molarity (M) and molality (m) of the toluene are ?
M=3.65*10^-5
To find the molarity (M) of toluene in the solution, we need to calculate the number of moles of toluene and then divide it by the volume of the solution in liters.
Step 1: Calculate the moles of toluene (C6H5CH3):
Molar mass of toluene (C6H5CH3) = (6 * 12.01 g/mol) + (5 * 1.01 g/mol) + (1 * 12.01 g/mol) = 92.14 g/mol
Moles of toluene = (volume of toluene in mL * density of toluene) / molar mass of toluene
= (25.0 mL * 0.867 g/mL) / 92.14 g/mol
= 0.236 mol
Step 2: Calculate the volume of the solution in liters:
Volume of the solution = volume of toluene + volume of benzene
= 25.0 mL + 135.0 mL
= 160.0 mL = 0.16 L
Step 3: Calculate the molarity (M) of toluene:
Molarity (M) of toluene = moles of toluene / volume of solution in liters
= 0.236 mol / 0.16 L
= 1.475 M
To find the molality (m) of toluene in the solution, we need to calculate the number of moles of toluene and then divide it by the mass of the solvent (benzene) in kilograms.
Step 1: Calculate the mass of benzene (C6H6):
Mass of benzene = volume of benzene * density of benzene
= 135.0 mL * 0.874 g/mL
= 117.99 g
Step 2: Convert the mass of benzene to kilograms:
Mass of benzene in kg = Mass of benzene / 1000
= 117.99 g / 1000
= 0.11799 kg
Step 3: Calculate the molality (m) of toluene:
Molality (m) of toluene = moles of toluene / mass of benzene in kg
= 0.236 mol / 0.11799 kg
= 1.999 m
Therefore, the molarity (M) of toluene in the solution is 1.475 M, and the molality (m) of toluene in the solution is 1.999 m.