I am stuck in this problem I need to calculate the molality first so I could find T but I don't know which one is the solvent and which one is the solution the problem is to calculate the freezing point of a solution containing 12.2g of benzoic acid, dissolved in 250g of nitrobenzene the freezing point of nitrobenzene is 5.7 C and its freezing point depression constant is 7.0 C/m. please help

Benzoic acid is a solid. Nitrobenzene is a liquid; therefore, mols benzoic acid is 12.2 g/molar mass benzoic acid. The solvent is nitrobenzene and you have 0.250 kg.

thanks

To calculate the molality of a solution, you need to identify the solvent and the solute. The solvent is the component that exists in a larger quantity, whereas the solute is the component that is dissolved.

In this case, the problem states that 12.2g of benzoic acid is dissolved in 250g of nitrobenzene. Based on this information, nitrobenzene is the solvent and benzoic acid is the solute.

To calculate the molality (m) of the solution, you can use the formula:

m = moles of solute / kilograms of solvent

First, let's find the number of moles of benzoic acid. The molar mass of benzoic acid (C7H6O2) is approximately 122.13 g/mol. To find moles, divide the mass of benzoic acid by its molar mass:

moles of benzoic acid = 12.2g / 122.13 g/mol

Next, convert the mass of nitrobenzene to kilograms:

mass of nitrobenzene = 250g / 1000 = 0.250kg

Now, substitute the values into the formula to calculate the molality:

m = (12.2g / 122.13 g/mol) / 0.250kg

Calculating this expression will give you the molality (m) of the solution.

Once you have determined the molality, you can use the freezing point depression formula to calculate the change in freezing point (∆T). The formula is:

∆T = Kf * m

In this case, the freezing point depression constant of nitrobenzene (Kf) is given as 7.0 C/m, and you have already determined the molality (m) using the previous calculations.

Finally, subtract the calculated ∆T from the freezing point of nitrobenzene (5.7 C):

Freezing point of the solution = Freezing point of nitrobenzene - ∆T

Calculating this expression will give you the freezing point of the solution.