The two solutions were combined in a microwave tube and put in the microwave for 30 minutes at 80oC. The solvent was evaporated under reduced…
22.5 27 385 629.78 -119.95 2 20 .75 23.5 30.9 642.45 1043.39 -132.36 3 20 1 22.6 34.9 1079.69 1747.14 -166.394 4 20 1.5 23 39.1 1448.29 2320.59 -147.5 Table 2: Average enthalpy of dissolution -141.25 KJ/mol Trial Hot H2O (mL) Cold H2O (mL) Tihot/ Ticold (celsius) Tf (celsius) q (J) 1 50 50 Table 3 Table 2 and 3: ∆T, the amount of H2O, and amount of MgCl2 used was recorded.…
Another possible error was that there was not specific temperature of the solution. As a substance’s temperature decrease, the substance’s density decreases (4). Temperature may have also impacted the rate at which the G2 had dissolved. If the temperature of a substance is altered to a temperature that is too warm or cold, it may affect the rate of the reaction. If a solution is heated too much, the particles will have moved faster than normal and collided more often (5).…
After each compound was added to the 50mL of water we used a magnetic stirrer and a stir plate to dissolve the compound and then a thermometer to measure both the initial and final temperatures of the compounds. Before we began our experiment it was necessary to look into the MSDS…
This made it effortless for H2O to detach from the substance when coming in contact with a heating source. This effectively left the substance anhydrous. This experiment determines the number of water molecules related to the hydrate. The experiment also helped formulate the empirical formula and percent composition of the hydrate…
This experiment will allow us to determine the molar mass of the unknown solute through calculating the difference in freezing point of the pure solvent and the solution with the unknown solute. This lab will show case one of the colligative properties of a solution. This property is dependent upon the number of solute molecules or ions and not the identity or chemical property of the solute. A common example is water which both freezes and melts at 0…
In the discussion an explanation is given that reiterates and further explains how the results were calculated. The lab report is concluded by revealing any experimental errors that may have caused a flaw in the results. Background This experiment uses the concept that by calculating the retention factors of an unknown compound by using thin-layer chromatography, recording the melting points, and determining the solubility of that unknown compound, that it is possible to determine what that compound is by comparing it to known compounds that have similar retention factors, melting points, and solubility.…
Conclusion Finding the molar mass of unknown solute resulted in choosing the tetradecanol as a possible answer for this lab report. I picked this compound name because the molar mass of a solute was closest to the teradecanol number. However, I think that my results deviated significantly from what I should get. I think that another possible answer for this experiment was a hexadecanol.…
The freezing point of the cyclohexanol was about 17.7°C, and the freezing point for the unknown solute mixed into the cyclohexanol was about 6.2°C. So the approximate change in temperature of the two freezing points was about 11.5°C. With this calculated information, the found molar mass of the unknown solute B was about 278.4g/mol, which is close to given molar mass of octadecanol. Conclusion-…
Retrieved October 2, 2016, from Virtual Chembook, http://chemistry.elmhurst.edu/vchembook/106Amixture.html 5. Kuan, E. (2012). A STUDY OF DISSOLVING ALKA-SELTZER IN DIFFERENT LIQUIDS. Retrieved October 2, 2016, 6. Zumdahl, S., & Zumdahl, S. (2007).…
INTRODUCTION The trends in physical properties of organic compounds such as boiling points and melting points can be deducted from their structures, including size (molecular weight, surface area), shape and functional groups. These factors significantly influence the strength of the intermolecular forces of attraction present; and the nature and strength of intermolecular forces determine the variations in boilingpoints of organic compounds. The boiling point of a liquid is the temperature at which its vapor pressure equals the external or atmospheric pressure. At this temperature, every molecules of the liquid acquire enough kinetic energy to overcome the intermolecular forces attracting them to the other molecules.…
The theoretical concepts that underlie the Hot Ice experiment involve a supercooled, supersaturated aqueous solution becoming a solid. When a liquid is cooled beyond its freezing point but remains liquid is known as supercooling or undercooling, and being supersaturated occurs when the solutes in a solution exceed the saturation point. The sodium acetate in a supercooled state will rapidly change into a solid with the addition of physical energy or a nucleation site. During the transformation of the liquid supercooled solution into solid crystalline formation produces heat in an exothermic reaction, hence the name hot ice.…
In this lab, five different ratios of two chemical solids, Urea and trans¬-cinnamic acid, were heated up in a Mel Temp apparatus until the final melting point was achieved. Each substance started as a solid in a capillary tube and when they reached the…
Introduction: Solubility is the “ability for a given substance, the solute, to dissolve in a solvent” . The effect of temperature on solubility is that when heat (energy) is added, it increases the speed on which molecules and particles move, therefore making it a quicker process. Where as with cooler temperatures there aren’t as many particles because the solvent doesn’t contain as much energy as warmer temperatures, therefore not dissolving as well as it could if it was warmer. To make jelly you first of all need to add boiling water to dissolve the sugar crystals and make sure they have completely dissolved before adding cold water to increase the amount, this is an example of the effect of temperature on solubility of sugar. The rate of solubility can depend on multiple factors such as the temperature of solvent, the size of the solute and how the solvent is stirred for example stirring time, big or small movements.…
If too much of the sample liquid entered the capillary tube, some was removed by lightly tapping the tube on a paper towel. In each of the capillary tubes the sample liquid was moved to the middle of the tube by lightly tapping it; once the liquid was in the middle both ends of the tube were sealed by plugging both ends with some Vaseline. The capillary tubes were then arranged in sequence along the tube holder with a space between the 3 groups. The alcohol bath was then prepared by placing dry ice into it in order to lower the temperature to around -15°C. Gloves or paper towels were used to handle the dry ice.…