In this lab, a metathesis reaction between an unknown metal carbonate (M2CO3) and calcium chloride (CaCl2), dependent on the ionic states of both compounds, allowed for identification of the metal through gravimetric analysis. Two grams of the metal carbonate were measured using an analytical balance and then dissolved in an aqueous solution with CaCl2 such that CaCo3 and a metal chloride formed from the reaction. The total mass of the metal carbonate was 112 grams per mole. Subtraction of the mass of CO3 from the total mass informed the metal’s identity: sodium. Due to the loss of precipitate and the utilization of two pieces of filter paper, a wide margin of error exists.
We began this investigation by suiting up in lab aprons and goggles, we then gathered our materials, found a lab station and got to work. We decided to start with the magnesium in hydrochloric acid first, we measured out 198.5 L of HCl and put it in the foam-cup calorimeter and took initial temperature reading. We then selected a piece of magnesium ribbon and found its mass: 0.01g. This piece was placed in the calorimeter and the lid was shut immediately to prevent heat from escaping. We “swirled” the liquid mixture in the calorimeter to ensure a reaction, and waited for a temperature change. After a few moments, the final temperature was recorded and DT determined.
This experiment studied the kinetics and the effects of solvent polarity of a solvolysis reaction. This reaction is a SN1 reaction in which the solvent (water) is the nucleophile. The reaction begins with the removal of a chloride ion; this is the rate determining step (slow step). Water is then added to the carbocation, forming a protonated alcohol. Lastly, a proton is removed by the present base. Since the first step is the rate determining step, it is a first-order reaction.
The fifth experiment of the semester entails a synthesis reaction geared towards analyzing the structure of a product. The starting material is isopentyl alcohol. When reacted with acetic acid with sulfuric acid as a solvent, isopentyl alcohol produces isopentyl acetate, which is the goal product, as shown in the reaction below:
“Enzymes are proteins that have catalytic functions” [1], “that speed up or slow down reactions”[2], “indispensable to maintenance and activity of life”[1]. They are each very specific, and will only work when a particular substrate fits in their active site. An active site is “a region on the surface of an enzyme where the substrate binds, and where the reaction occurs”[2].
The primary problem that would occur if magnesium were to be substituted by carbon is that carbon and oxygen form the compound CO2 when they react, which is in a gaseous state above -78.5 degrees Celsius, which is far below the temperature at which the experiment was performed. In this state, it is difficult to contain carbon dioxide gas without an airtight container. This experiment is not possible with an airtight container, since oxygen must enter to react with the carbon, and therefore some the carbon dioxide would inevitably escape, rendering the results invalid.
Light dependent reactions are the effects that occur in photosynthetic organisms in response to solar energy and is the initial process of photosynthesis. Another name for light dependent reactions is, non-cyclic photophosphorylation. The site of these reactions occurs within the chloroplast in what is known as the Thylakoid membrane. Light is absorbed by something called photosystems (PSI AND PSII) and is part of all photosynthetic organisms. The light energy collected in this process will later become chemical energy. The process starts out with the excited electrons in PSII and then PSI. These electrons become excited from the absorption of light. The high energy electrons in PSI go down something called the electron
The compound that was assigned to be tested and the identity to be discovered was blue in color. Once 0.5028 grams of the blue compound was weighed out it was combined with 5 mL of distilled water. initially the unknown compound didn’t seem to dissolve in water. However, after a few minutes of constant stirring the substance dissolved completely. Thus indicating that the cation in the unknown compound was Cu2+. The identity of the cation had to be confirmed therefore a flame test had to be preformed. Once the solution was placed over the Bunsen burner the flame turned green confirming that the cation was Cu2+. To determine the character of the anion 0.1087 grams of the unknown compound, and 0.5109 grams of Na2CO3 was measured. Both solids were
Calcium is a solid, with a melting point of 〖842〗^0C. The boiling point of Calcium is 〖1484〗^0C. It is a shiny, soft substance. The estimated crustal abundance of Calcium is 4.15*〖10〗^4milligrams per kilogram. The estimated oceanic abundance of Calcium is4.12*〖10〗^2. This metal can be used to remove oxygen, sulphur, and carbon from certain alloys. Since calcium has a high reactivity with common materials it is rarely used as a metal. Calcium metal is used as a reducing agent in preparing other metals such as thorium and uranium. Calcium is also used in a compound mixture of calcium carbonate; used as a building material (limestone).
The materials for this experiment include Magnesium, a Bunsen burner, a analytical balance, and an evaporation disk. Beginning the experiment the empty evaporating dish is placed on the analytical balance and the mass is recorded. Then, Magnesium is placed in the evaporating dish and put back on the analytical balance and the
To be able to identify what kind of macromolecules a solution has, it has to be tested to be able to identify what macromolecules are present in the solution. Here we used only one test for each macromolecule that we are testing for. We tested for RNA, DNA, protein, sugar, starch, and lipid macromolecules. Using these kinds of test we were able to figure out, that we can detect what kind of macromolecules are present in a solution almost with full accuracy.
It is essentially using the the mass of the product to figure out the original mass that we are looking for. Thus, the purpose of our experiment was to compare the final mass in our reaction to the initial mass and determine the change in mass. In our experiment, we utilized the hydrate cobaltous chloride. Hydrates are crystalline compounds in which one or more molecules of water are combined with each unit of salt. Cobalt (II) chloride hexahydrate is an inorganic compound which has a deep rose color in its hydrated form.
The results from the gel electrophoresis were inconclusive so students selected their genotype, with the results shown in Table 1. The controls were successful with the (+/+) homozygous, (-/-) homozygous, and heterozygous lanes having bands at 941, 641, and both 941 and 641 respectively. The class allelic frequencies were 56.3% for p and 43.8% for q, indicating that slightly more individuals had the Alu insert on their chromosomes (Table 2). When the Hardy-Weinberg equation was applied, there were some discrepancies as shown by Table 3 between the observed and calculated frequencies. The p frequency was observed at 10% higher than Hardy-Weinberg while the q frequency was observed at 10% lower.
All biological processes require a constant supply of energy. The fabrication and regulation of energy is a result of catalytic reactions that occur in cells by enzymes. Enzymes typically contain a few active sites that enable substrates (reactants) to bind to their designated enzyme and form an enzyme-substrate complex, to then release the product (Alberte J. , Pitzer T. , Calero K.). In order for an enzyme to release a product, the reactant molecules must absorb enough energy from their surroundings to reach the unstable transition state and form new bonds at a faster rate without the denaturization of the enzyme. Enzymes have sets of conditions at which they are enabled to work properly, known as the optimal condition. For experiment 4,
Photosynthesis is the process where plants transform light energy usually from sunlight into chemical energy and its balanced equation is 6CO2 + 6H2O –light energy----> C6H12O6 + 6O2 (Elsevier B.V.,LiveScience). Photosynthesis has major byproducts including water, glucose and starch(which is produced in the plant), and last but not least; oxygen. There are numerous amounts of plants all around the world producing CO2 necessary for human survival. However, the photosynthesis cycle is not visible which results in the plants appearing like they are not doing anything. One way to clearly prove that plants are indeed performing photosynthesis is to observe the plants giving off oxygen; which is one of the most important results of
The goal of the project was to characterize an "unknown" organic acid in order to make a proper identification of the acid, while learning proper techniques for scientific measurement and analysis of error.