What are the major sources of error in the freezing point depression experiment?

What are the major sources of error in the freezing point depression experiment?

what were major sources of error in this experiment? naphthalene being lost because it solidified, not reading thermometer correctly, not letting all of solidified naphthalene melt before measuring FDP.

How do you find the molar mass of unknown using freezing point depression?

Use the freeing point depression (ΔTf) to calculate the molality of the solution. Then use the molality equation to calculate the moles of solute. Then divide the grams of solute by the moles to determine the molar mass.

What variables would cause the differences in freezing point depression?

The freezing point depression due to the presence of a solute is also a colligative property. That is, the amount of change in the freezing point is related to the number of particles of solute in a solution and is not related to the chemical composition of the solute.

How will you know you’ve reached the freezing point of the solution?

To reach the freezing point of the solution, the temperature has to be lower than it is in the case of the pure solvent. Therefore, the temperature at which the solution freezes is lower than that of the pure solvent. The change in the freezing point is proportional to the amount of solute added.

How do you find molality from freezing point?

The freezing point depression ∆T = KF·m where KF is the molal freezing point depression constant and m is the molality of the solute. Rearrangement gives: mol solute = (m) x (kg solvent) where kg of solvent is the mass of the solvent (lauric acid) in the mixture. This gives the moles of the solute.

How does molar mass affect the freezing point?

Thus, as the molar mass increases, the freezing point depression decreases . That is, increasing the molar (or molecular) mass will have a smaller effect on the freezing point.

What does melting point depression mean?

Melting-point depression is the phenomenon of reduction of the melting point of a material with reduction of its size. This phenomenon is very prominent in nanoscale materials, which melt at temperatures hundreds of degrees lower than bulk materials.

What is molal depression constant?

Molal depression constant is defined as the depression in freezing point produced when 1 mole of solute is dissolved in one kg (1000 g) of the solvent. molal depression constant kf is defined as the depression in the freezing point of a solution whose molality is one .