Freezing Point Depression Lab Report

4. It is an advantage to choose a solvent that has a large value for kfp because the larger value produces a larger drop in freezing point. Having a larger drop in freezing point is an advantage because it allows for the data to be more easily read. A large drop in freezing point also produces more significant figures and more significant figures means the calculated molar mass is more precise.

The freezing point depression constant for water that was experimentally determined in this analysis was 0.0479 °C/m, which was derived from the slope of the trend line in Figure 4. This is significantly lower than the constant stated in the literature of 1.86 °C/m.1 The freezing point temperature determined via cryoscopy should have been much lower in the high sucrose concentration solutions.

The freezing point constant (Kf) of water is 1.86 °C m-1. Each mass amount and Van’t Hoff factor was calculated then analyzed in a table.

Other substances that dissolve in water also lower the freezing point of the solution. The amount by which the freezing point is lowered depends only on the number of molecules dissolved, not on their chemical nature. This is an example of a colligative property. In this project, you'll investigate different substances to see how they affect the rate at which ice cubes melt. You'll test substances that dissolve in water (i.e., soluble substances), like salt and sugar, as well as substances that don't dissolve in water (i.e., insoluble substances), like sand and pepper. Which substances will speed up the melting of the ice?

In this lab, the molar mass of a volatile liquid is determined based on its physical properties in the vapor state. In order to calculate the molar mass, the mass, temperature, pressure, and volume is measured independently and then converted to the correct units. Sample C was obtained at the beginning of the experiment, which was later informed to be ethanol. Based on the calculations made, the molar mass of the volatile liquid was 95.9 g/mol. However, compared to the known value of 46.1 g of ethanol, the value measured had a 108% error. Unfortunately, this was a very big percent error and may have been caused by incorrectly measuring the volume of the gas. Using the ideal gas law, the molar mass of a volatile compound was calculated in order

Introduction: The experiment's goal was to determine the freezing point of a pure solvent and the freezing point depressions of two solutions. The freezing point and the freezing point depressions were determined by graphing the temperature of the pure solvent and two solutions as they cooled and observing when crystals first formed.

Purpose: The purpose of this laboratory was to gain an understanding of the differences between the freezing points of pure solvent to that of a solvent in a solution with a nonvolatile solute, and to compare the two.

An instant cold pack is a device which is composed of 2 sacks, one which contains water, and the other with another chemical. When the user wishes to activate the cold pack, she squeezes it, and breaks the boundary between the water and the chemical. This causes an endothermic reaction as the water dissolves the chemical. The reaction then lowers the pack’s temperature by absorbing heat from the surroundings. Cold packs typically utilize the chemicals ammonium nitrate, calcium ammonium nitrate, or urea. A cold pack using ammonium nitrate will typically hit a low of 1.67℃ for 10 to 15 minutes. However, for the purposes of the first portion of the experiment, the chemicals being tested were ammonium chloride, sodium chloride, and calcium

Introduction The purpose of this lab was to explore the colligative properties, in this case freezing point and freezing point depression, of the solvent p-xylene. The freezing point of p-xylene was obtained using the MicroLab program and a thermistor temperature sensor. From this data, the freezing point depression constant, kf, could be found, as well as identifying three unknown solutes by calculating their molar masses.

The purpose of this experiment is to identify an unknown substance by measuring the density and boiling point. I will be able to conclude which substance is my own from a list of known options stating what its real boiling point and density is.

First, students find the average temperature of the solvent by averaging the two temperatures found with the test tube with only the t-butyl alcohol. Students then find the freezing point of the t-butyl alcohol and the unknown mixture through using an equation that goes Temp =(m2b1-m1b2)/(m2-m1). From our lab group experiment, the average temperature of the pure t-butyl alcohol was 23.1 degrees Celsius and the mixture was 12.0 degrees Celsius. After finding the two temperatures, we subtracted the average temperature of the t-butyl alcohol and the freezing point of solution to get 11.1 degrees Celsius. Then, we divided the 11.1 by 8.37 °C/m to get the molality, which was 1.32616 m. Afterwards, we found the moles of solute by multiplying the kilograms of the t-butyl alcohol (0.01898 kg) by the molality to get 0.025170 moles. To find the molar mass, you divide the mass of the unknown by the moles of the unknown. When our group did these steps, we got an answer of 125.5 g/mol as our final

The objectives of this lab are, as follows; to understand what occurs at the molecular level when a substance melts; to understand the primary purpose of melting point data; to demonstrate the technique for obtaining the melting point of an organic substance; and to explain the effect of impurities on the melting point of a substance. Through the experimentation of three substances, tetracosane, 1-tetradecanol and a mixture of the two, observations can be made in reference to melting point concerning polarity, molecular weight and purity of the substance. When comparing the two substances, it is evident that heavy molecule weight of tetracosane allowed

To achieve this, the final value from each thermocouple was set to be equal to the warm water bath temperature (370C), and the initial reading was set equal to the ice water bath temperature. Thus, for each thermocouple an equation was obtained using the two points to convert voltage readings to temperature. An example of the calibration for one of the thermocouples is shown in Appendix II.

Freezing point depression is a colligative property observed in solutions that results from the introduction of solute molecules to a solvent. The freezing points of solutions are all lower than that of the pure solvent and are directly proportional to the molality of the solute.

As stated, our solvent in this lab will be tert-butanol. We start by recording the freezing point of this substance without anything added. Then, we add various