The purpose of this lab was to determine the melting and freezing point of an unknown (Q) substance and to identify the unknown substance based on the melting and freezing properties. First, to start the lab, a double ring system was set up for a hot water bath. Next, unknown Q was examined and observations about the solid were taken at the lab station. Next, a test tube that contained unknown Q was placed onto a test tube clamp. Next, the test tube clamp was attached to the ring stand and it was submerged into the hot water bath. Next, the room temperature was recorded of unknown Q. Next, a bunsen burner was lit and the temperature was recorded in thirty second intervals while unknown Q warms up until unknown Q is completely liquified.
A hot plate was placed under the ring stand. 50 mL of 3.0 M NaOH in a 250 mL beaker and a stir bar was placed in the beaker. The beaker with NaOH was placed on the hot plate and 3.75 grams of NaAlO2*5H2O was placed in the beaker. The temperature probe was placed in the beaker with the solution, not touching the bottom of the beaker. The solution was heated and stirred till the solution dissolved.
The temperature probe was kept in the calorimeter until the temperature had been stabilized and was calibrated. A beaker was placed on a hot plate with dial turned between three and four. Another 100.00 ml of deionized water was added while the beaker is heating up. Using the temperature probe, the beaker was measured
The purpose of this lab was to be able to use physical characteristics to determine the identity of an unknown compound. The data from this experiment classified aluminum as metallic; ascorbic acid, paraffin, palmitic acid, sucrose, graphite, and water as molecular; sodium chloride as ionic. In order to determine this, 3 tests were conducted. The first test was to test the conductivity of each substance at room temperature. In this test, only graphite and aluminum conducted.
Unknown Lab Report Unknown # 25 By: Jenna Riordan March 19, 2018 Bio 2843 1. Introduction Microbiology is the study of microorganisms found in all different environments throughout Earth, from the hot thermal vents at the bottom of the ocean to the ice at the top of a mountain.
The lab started off by measuring critical materials for the lab: the mass of an an empty 100 mL beaker, mass of beaker and copper chloride together(52.30 g), and the mass of three iron nails(2.73 g). The goal of this experiment is to determine the number of moles of copper and iron that would be produced in the reaction of iron and copper(II) chloride, the ratio of moles of iron to moles of copper, and the percent yield of copper produced. 2.00 grams of copper(II) chloride was added in the beaker to mix with 15 mL of distilled water. Then, three dry nails are placed in the copper(II) chloride solution for approximately 25 minutes. The three nails have to be scraped clean by sandpaper to make the surface of the nail shiny; if the nails are not clean, then some unknown substances might accidentally mix into the reaction and cause variations of the result.
The Unknown Identification Lab was an experiment that provided the opportunity to apply all the tests that were learned in the semester of lab, to identify the two bacterias that remain unknown. Gram- staining and two other tests will be used to identify the unknowns. This experiment is crucial to the understanding of each test, and can benefit in the ability to identify the characteristics of specific bacteria. Having a clearer understanding of the bacteria can further the research of bacteria for medicine, such as antibiotics. The understanding can also help the development of research in the environment.
In chemistry, elements have properties that distinguish them from one another. Despite the various chemical properties, one of the most important physical properties is a property known as density. Density was first discovered in 250 BC by the Greek mathematician Archimedes when he compared real and fake gold by placing both in water. The key principle is that density will affect whether objects float or sink. If an object has a higher density than its surroundings, it will sink.
Modifications of this procedure include the use of hot plates instead of Bunsen burners, and heating t-butyl alcohol to 60-65 ℃ instead of 50 ℃. Other modifications include the use of weighing boats to measure an amount of unknown instead of weighing paper, and completing one run of unknown 2 instead of two runs of unknown 2. Summary of
It can be hypothesized that the water in the product affected the melting point
I will put the thermometer into the beaker and stir the water, leave the thermometer till the temperature stays constant.-this will give the normal water temperature. 13. I will take the water out the beaker and wipe it dry. 14. I will activate the heat packs wait for a minute put thermometer onto the copper to see the temperature 15.
Part 2 of the laboratory hypothesizes that different PEG precursor combinations will have an effect on the modulus of the material due to the differences in mesh structure. Unlike part 1, part 2 focuses on variation in mesh structure due to the polymerization of 2, 4, and 8 arm PEGnorb with 2 and 4 arm PEG thiol, rather than the impact of polymerization time. Table II displays the precursor combinations, the resulting hydrogel modulus, and the mesh size of experimental groups 1-2, 4-5, and 7-8. Figure 2 (a) and (b) display the modulus of each group and the mesh size of select groups, respectively. Although trivial, the minimum modulus displayed in Figure 2 (a) is group 1, a combination of 2 arm PEGnorb, or PEG 2k, and PEGdithiol, or 2SH, of
Properties of Substances Express Lab 1)The purpose of this lab was to compare the physical properties of different types of solids and how the properties of solids are determined by their intermolecular forces and their intramolecular bonds. Then we were to classify each type of solid as either ionic, metallic, non-polar molecular, polar molecular, or network. Paraffin wax classified as a non-polar molecular, Silicon dioxide was classifies as a network, Sodium chloride was classified as ionic, Sucrose was classified as polar molecular and Tin was classified as metallic. (2)The intermolecular forces that are present in Paraffin wax are dispersion forces, because it is non-polar and carries a negative charge. Followed by Sucrose that has
I. Introduction This experiment uses calorimetry to measure the specific heat of a metal. Calorimetry is used to observe and measure heat flow between two substances. The heat flow is measured as it travels from a higher temperature to a lower one. Specific heat is an amount of heat required to raise the temperature of one gram of anything one degree Celsius. Specific heat is calculated using several equations using the base equation: q=mc∆T II.
In the beginning of the experiment, both planets would have around the same temperature; however, the thinner atmosphere would eventually be hotter, then subside toward the end of the experiment. Two beakers with differing thicknesses of plastic wrap, with a lamp overhead, represents this scenario. According to a group’s data (their group number to be determined), both beakers with differing atmospheres steadily increase by 1℃ respectively until the fifth minute, where the planet with the thinner atmosphere has a hotter surface temperature. After four more trials, the beaker with the thinner atmosphere would increase until both beakers are around the same temperature again. In another group’s data (their group number also inconclusive), both
4.2 Antifreeze Fluids with IBPs As studies show in Dow Chemical Company (DCC), the glycerol-water solution becomes slushy when it freezes (107) indicated with our studies shown in Figure 41(a). Specifically, the experiment shows the interaction between 20% glycerol and IBPs. For example, at 274.2 K the right-side peak becomes shorter because it reaches its freezing point of the 20% glycerol at 268.5K (83). Then, when the temperature is lowered to 241.1 K, the inhomogeneity of the system due to the glycerol is observed. Studies from DCC has shown that when lowering the temperature, the slush becomes increasingly viscous (107).