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.
Once the material was acquired, 1.0094 grams of Aluminum were weighed and then transferred to a 250mL beaker. The 250mL beaker continued to remain in use for the next few steps. 1.4M KOH solution was added to the Aluminum sample that was previously obtained. For gas to escape the lab, there was a fume
Temperature is important, since above 250C° and below 50C virtually no crystallization occurs. Around 14°C is the optimum temperature for rapid crystallization, but also the presence of solid particles (e.g. pollen grains) and slow stirring result in quicker crystallization. Usually, slow crystallization produces bigger and more irregular crystals. During crystallization, water is freed.
After identifying the first cation, the following procedures identified the second cation, which was barium or calcium. The second cation was identified by using the liquid portion of the solution mixed with hydrochloric acid and separated from the white precipitate, silver chloride after being centrifuged. Ammonium carbonated, which serves as to help confirm the presence of either barium or calcium cation, was added and stirred to this existing solution, causing the solution to become cloudy and white. Afterwards, the solution was heated and occasionally stirred in a hot water bath, the white precipitate began settling at the bottom of the test tube, which could be either barium carbonate or calcium carbonate. Once the test tube was left to cooldown, it was
The objective of this lab is to see the effect of hot and cold rolling of Al 5083. And to see the effect of cooling on a casted Aluminum 7075 alloy. Once the alloy is cast it will be cold rolled to 20, 40, 60, and 80% reduction and hot rolled to 40, 60, and 80% reduction samples. The rolling will produce a change in the hardness and grain size. The hardness will be tested using a Rockwell hardness test for the grain size measurements we will etch and anodize the surface.
The purpose of the lab was to discover the properties and the trends of the alkaline earth metals. In part A, the trend was as the atomic number increase in the alkaline earth metals the elements are more reactive. The alkaline earth metals each have two electrons in their outer shell and because all electrons want to become stable they are ready to give up the two electrons. When they are combined with water, the chemical reaction occurs differently based on each element.
Pertaining to the appearance of the oil and water before the reaction occurs, oil “sits” on top of the water because oil is less dense than water, and therefore rests on the surface of the water. The Alka-Seltzer, or effervescent tablet, reacts with the water and produces bubbles of carbon dioxide gas. This gas is less dense than both the water and oil, so it travels the the surface of the liquid, pulling a small amount of the colored water with it and creating the “lava lamp” effect. The chemical reaction that is occurring is an acid-base reaction, and results from the reaction between the ingredients in the Alka-Seltzer tablets.
Since the crude solid’s melting point range coincided with the purified melting point range of the purified solid, the recrystallization process indicates that the compound of interest was the same, only more refined. Both ranges were small, with the recrystallized melting point values being more precise, therefore indicating that the purity was evident. Meanwhile, the distillation for the liquid resulted in two different refractive indexes which varied significantly from each other. While this could be apprehended as a sign of impurity, the large difference between the two refractive indexes of 0.1769 indicates that the distillation process did not produce a very pure liquid from the start. The temperature could have a role in this large difference between the crude and the purified liquid sample as the refractive index can change with temperature 2.
After being dissolved in a minimal amount of hot 95% ethanol, crystal formation began again once water was added until the solution looked semi-opaque. After cooling, the flask was placed into an ice bath for
The purpose of this experiment is to prove that the amount of crystallization will be greater when some crystals are already present. To conduct the experiment, 6 jars were prepared. Four cups of sugar and two cups of water were combined in a pot and boiled on the stove until a temperature of 215 degrees. After removing from heat, an additional 12 tablespoons of sugar were added to the solution as it cooled. Equal amounts of the cooled solution were poured into jars.
Alkaline Earth Metals Lab Report INTRODUCTION: This lab is designed to find a pattern in reactivity of different alkaline earth metals. Alkaline earth metals are elements in group 2 of the Periodic Table of Elements. These include Calcium, Magnesium, Barium, Strontium, Beryllium, and Radium, all of which are found in natural compounds and react with water, except for beryllium. Groups are sometimes called families, because they share chemical properties, behaviors, and reactions, due to the fact that they have the same valence electron shell configuration.
The amount of water collected through the distillation process was small as there was too much seawater used and therefore it was unable to fully evaporate. If the water had been evaporated the results would have been clearer that the water was pure. In the second part of the experiment the water was tested before hand to ensure that the water was seawater using silver nitrate and then later tested to find out what ionic compound it had in it, sodium chloride. Glass bead were placed into the pear-shaped flask to control the boiling water.
Introduction and Historic Background Sodium chloride is also known as salt. The molecular formula for sodium chloride is NaCl. NaCl has a molar mass of 58.443 grams. Sir Humphry Davy discovered sodium chloride in 1807. He was able to extract sodium from its compounds, which included sodium’s connection with chlorine.
One is that the base was not exactly the right Molar solution wanted but was only off by roughly 0.001. In this experiment there were a few risks in doing it so certain measures were taken to make sure nothing happened. As the experiment was dealing with an acid, lab coats and goggles were warn. Also as there was the chance of broken glass, when using any glassware it was to be handled with care.
In this research paper, I am going to investigate on how the concentration of Sodium Chloride (NaCl) solution affects the volume of the gases (Oxygen gas and Chlorine gas) at the anode during the electrolysis of sodium chloride solution. In my previous chemistry classes, I have learnt that concentration affects the majority of the gas produced at the anode. This made me wonder, how does the ratio of oxygen gas to chlorine gas produced at the anode vary at the electrodes. This made me formulate the research question: How does the concentration of Sodium Chloride solution affect the ratio of oxygen gas to chlorine gas produced at the anode during the electrolysis of Sodium Chloride solution? This area specifically interests me because it is still
