Molar Mass Of Solute Lab Report
Determining the Molar Mass of an Unknown Solute by Freezing Point Depression
Introduction: Colligative properties of solutions are only influenced by the concentration of solute particles and are independent of the nature of the solute. Some examples of colligative properties are boiling point elevation, vapor pressure lowering, and freezing point lowering (depression) (Brown, 542). For a substance to freeze, the kinetic energy of the particles must be low enough for the attractions to arrange the molecules in one position in a crystal structure. The freezing point of a solution is the temperature at 1 atm of pressure when both the solid and liquid phases are in equilibrium (Brown, 545). Solute particles cause the …show more content…
These contaminants could have impacted the mass a very small amount, but not significantly. In the future, the test tubes used should be more thoroughly examined to remove any potential impurities. A last experimental error that could have also had a small effect on the molar mass was the thermometer was not properly calibrated. In theory, water freezes at 0°C, but in the first part of the lab, the thermometer read 0.2°C for the freezing point (Figure 1). However, this inaccurate reading would have had a minimal effect on the results, because the difference in the freezing point was calculated. In the future, the thermometer should be calibrated before the experiment to ensure the temperatures read are accurate. The results of the experiment align with discoveries made by other scientists. According to research conducted by Seoul National University of Technology and the University of Michigan, the temperature that water with compounds, especially cholesterol, freezes is lower than pure water (Lee et. al, 2008). The research by the two universities helps to support that pure water freezes at a higher temperature than a solution or that solutes dissolved in solvents affect colligative
Introduction: Colligative properties of solutions are only influenced by the concentration of solute particles and are independent of the nature of the solute. Some examples of colligative properties are boiling point elevation, vapor pressure lowering, and freezing point lowering (depression) (Brown, 542). For a substance to freeze, the kinetic energy of the particles must be low enough for the attractions to arrange the molecules in one position in a crystal structure. The freezing point of a solution is the temperature at 1 atm of pressure when both the solid and liquid phases are in equilibrium (Brown, 545). Solute particles cause the …show more content…
These contaminants could have impacted the mass a very small amount, but not significantly. In the future, the test tubes used should be more thoroughly examined to remove any potential impurities. A last experimental error that could have also had a small effect on the molar mass was the thermometer was not properly calibrated. In theory, water freezes at 0°C, but in the first part of the lab, the thermometer read 0.2°C for the freezing point (Figure 1). However, this inaccurate reading would have had a minimal effect on the results, because the difference in the freezing point was calculated. In the future, the thermometer should be calibrated before the experiment to ensure the temperatures read are accurate. The results of the experiment align with discoveries made by other scientists. According to research conducted by Seoul National University of Technology and the University of Michigan, the temperature that water with compounds, especially cholesterol, freezes is lower than pure water (Lee et. al, 2008). The research by the two universities helps to support that pure water freezes at a higher temperature than a solution or that solutes dissolved in solvents affect colligative