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What is the boiling point of a solution that contains 50.0 g of FeBr3 in 200.0 g of water?

User Joe Flack
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1 Answer

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Answer:

= 100.471 °C

Explanation:

To determine the boiling point of a solution containing a solute (in this case, FeBr3) dissolved in a solvent (in this case, water), we can use the following equation:

ΔTb = Kb x molality

where ΔTb is the boiling point elevation, Kb is the boiling point elevation constant for water (0.512 °C/m), and molality is the molality of the solution, which is defined as the number of moles of solute per kilogram of solvent.

First, we need to calculate the molality of the solution:

molality = moles of solute / mass of solvent (in kg)

To calculate the moles of FeBr3, we need to divide the mass of FeBr3 by its molar mass:

molar mass of FeBr3 = 55.85 g/mol (for Fe) + 3 x 79.90 g/mol (for Br) = 271.55 g/mol

moles of FeBr3 = 50.0 g / 271.55 g/mol = 0.184 moles

mass of water = 200.0 g = 0.2 kg

molality = 0.184 moles / 0.2 kg = 0.92 mol/kg

Now we can calculate the boiling point elevation:

ΔTb = Kb x molality = 0.512 °C/m x 0.92 mol/kg = 0.471 °C

Finally, we can calculate the boiling point of the solution:

boiling point of solution = boiling point of pure solvent + ΔTb

The boiling point of pure water at standard pressure is 100 °C. Therefore, the boiling point of the solution is:

boiling point of solution = 100 °C + 0.471 °C = 100.471 °C

So the boiling point of the solution containing 50.0 g of FeBr3 in 200.0 g of water is approximately 100.471 °C.
User Richard J
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