Calculate the molecular mass of the nonionic solutes: 64.3 g of solute in 390 g of water raises the boiling point to 100.680 degrees C.

To calculate the molecular mass of the nonionic solute, we need to use the formula for the elevation of boiling point:

ΔTb = Kbp * m,

where ΔTb is the boiling point elevation, Kbp is the boiling point elevation constant of the solvent, and m is the molality of the solute.

In this case, we are given that the boiling point is raised to 100.680 degrees C, which means the boiling point elevation (ΔTb) is 100.680 degrees C - 100 degrees C = 0.680 degrees C.

The boiling point elevation constant (Kbp) for water is approximately 0.512 degrees C/m.

Now, let's calculate the molality (m). Molality (m) is defined as the number of moles of solute divided by the mass of the solvent (in kg). We need to convert the masses to moles and then divide by the mass of the solvent:

Mass of solute = 64.3 g
Mass of water = 390 g = 0.39 kg

Now, let's calculate the molality:

m = (moles of solute) / (mass of water in kg)

To find the number of moles of the solute, we need to use the formula:

moles = mass / molar mass

Since we are trying to calculate the molar mass, we rearrange the equation as follows:

molar mass = mass / moles

Let's find the moles of solute:

moles of solute = mass of solute / molar mass of solute

Since the mass of the solute is given as 64.3 g, now we need to find the molar mass of the solute.

Finally, we can calculate the molar mass:

molar mass = mass of solute / moles of solute.

Let's plug in the values:

ΔTb = 0.680 degrees C
Kbp = 0.512 degrees C/m
Mass of water = 0.39 kg
Mass of solute = 64.3 g

First, calculate the molality:

m = 64.3 g / molar mass of solute

Next, calculate the number of moles of the solute:

moles of solute = 64.3 g / molar mass of solute

Now, rearrange the equation to solve for the molar mass of solute:

molar mass of solute = 64.3 g / moles of solute.

You can plug in the values and calculate the molar mass of the solute.

Isn't your subject chemistry?

boiling point eleveation= Kb*molality
.680=molessolute/kgwater * .52

solve for molessolute, then molessolute=massingrams/molemass and you can solve for massingrams.