A solution is made using 199.7 g of toluene and 80 g of benzene. What is the molality of the tolunene in the solution?

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