We resulted that lead, silver, and copper are the strongest oxidizing agents, and that magnesium and zinc are the weak oxidizing agents. The strong oxidizing agent oxidized the weak oxidizing agent and in turn the strong oxidizing agent got reduced while oxidizing the weak agent. When a reaction occurred, the solid metal reduced the ion, and in turn made it the more reactive metal. In part two we used a solvent extraction technique to derive an activity series for the halogens. With the use of this technique we placed chlorine, bromine, and iodine into solutions containing chloride, bromide, and iodide.
A) Hydrogen bonds are strong enough to confer structural stability, for example in DNA. B) Hydrogen bonds are weak enough to be easily broken (weaker than covalent bonds). C) They contribute to the water solubility of many macromolecules. D) All of the above Answer: D Page Ref: Section 5 27) London dispersion forces are attractive forces that arise due to A) infinitesimal dipoles generated by the constant random motion of electrons. B) permanent dipoles of molecules containing covalent bonds between atoms of very different electronegativities.
Introduction Nucelophilic substitutions are chemical reactions in which an electron rich nucleophile attacks the electron poor electrophile1. There are two classes of nucelophilic reactions – SN1, and SN2. The SN1 reaction is a 2 step, uni-molecular reaction, which is independent of the nucleophile. It requires a highly substituted electrophile since there is a formation of a carbocation in its rate determining step, good polar protic solvents which stabilize the carbocation and a good leaving group1. On the other hand, a SN2 reaction is a concerted, bimolecular reaction which has one slow, transition state1.
pH > 7 is alkalinity environment that will bind hydrogen ion, and pH < 7 is acidic environment that will donate hydrogen ion. On the other hand, increasing hydrogen ion concentration will reduce the bound metal cation concentration. Decreasing hydrogen ion concentration will increase the hydroxyl ion concentration (M. Chaplin, 2004). Enzymes are one of the most efficient catalysts in biochemical reactions. They are used to speed up the reaction rates by providing an alternative reaction pathway of lower activation energy, which is the minimum energy that requires for reactions occur.
Answer to focus question: Since it is amphoteric, it will act as an acid if reacts with base and act as a base when reacts with acid. So with both acid and base it will form salt. 3. Confidence report. I believe we did our procedures accurately.
LAH is highly reactive and will reduce acid chlorides, esters, carboxylic acids, amides, and nitriles as well as aldehydes and ketones. NaBH4 is less reactive and therefore more selective than LAH: it reduces aldehydes and ketones, but not carboxylic acids and amides, and only slowly reduces esters. NaBH4 is much safer to handle than is LAH, making it a good choice whenever the functional group to be reduced is an aldehyde or ketone. The purpose of the below methodology isto synthesize meso-hydrobenzoin from benzyl using the reducing agent sodium borohydride. Reaction and Mechanism: Formation of meso-hydrobenzoin | | Benzil | + | Sodium Borohydride | → | Hydrobenzoin | | C14H10O2 | | NaBH4 | | C14H14O2 | | | | | | | Molecular Wight | 210.23 g/mol | | 37.83 g/mol | | 214.26 g/mol | Observed Mass/Volume | 400 mg | | 150 mg | | 354.4 mg | Observed Moles | 1.902 mmol | | 3.96 mmol | | 1.65 mmol | Theoretical Yield | | | | | 407.52 mg | Percent Yield | | | | | 88.5 % | Theoretical Melting Point | 94-96 °C | | | | 137 °C | Observed Melting Point | | | | | 136.4-137.3 °C | Calculations: Observed Moles ofBenzil-0.2 g of Benzil x 1 mol210.23gmol=0.000951 mol→0.951 mmol x 2 reaction doubled=1.902 mmol Observed Moles ofSodium Borohydride-0.075 g of Sodium Borohydride x 1 mol37.83gmol=0.00198 mol→1.98 mmol x 2 reaction doubled=3.96 TY-0.000951 mol x 1
This is used when a weak acid is being used in the reaction as it acid does not fully dissociated and there is an A- value. This is the equation used for reaction (ii) as it used ClCHCOOH as the acid. Results, Observations and Discussion: (ii) 0.25M HCl | (iii) 0.5M Cl2CHCOOH | (iv) 0.125M HCl | Time(mins) | Vol (Na2S2O3) | Time(mins) | Vol(Na2S2O3) | Time(min) | Vol (Na2S2O3) | 0 | 0.46 | 0 | 0.4 | 0 | 0.33 | 6 | 0.44 | 8 | 0.4 | 6 | 0.28 | 12 | 0.4 | 16 | 0.36 | 12 | 0.24 | 18 | 0.36 | 24 | 0.29 | 18 | 0.22 | 24 | 0.32 | 32 | 0.26 | 24 | 0.2 | 30 | 0.28 | 40 | 0.2 | 30 | 0.19 | Calculations: Finding Kobs - (ii) -dI2dt=0.005
It may also be a sign of normal aging or a hallmark of pathologic processes [79-82]. The peroxynitrite anion (ONOO―) is a highly reactive molecule [83-86] and has low diffusion distance in biological tissue [87]. The most prominent analyzing marker for protein oxidation is carbonyl contents of proteins [88-91]. Carbonyl appears (C=O) as a consequence of oxidative modification of the side chains of lysine, proline, arginine and threonine [92]. Determination of protein C=O groups as biomarker of oxidative stress has advantages over measurement of other oxidative.
Introduction Chemical reactions and how they behave are a keystone not only in the scientific community and in scientific education, but also in daily functions and the biology of living organisms. Understanding how chemicals can affect their reactions and the pH of the solution they are in is important in maintaining balance in the ecosystem as well as the human body and other organisms. In this experiment, acids and bases at equilibrium with an indicator will be used with a spectrophotometer to calculate the equilibrium constant and pKa for Bromothymol Blue. Materials and Methods For part 1 of the experiment, obtain a 50 mL sample of sodium phosphate buffer solution and pour the sample into a 150 mL beaker. Take note of the
The standard method for preparing amides was used. The amine was acetylated to protect the amino group during the permanganate oxidation done next. This step was crucial to the percent yield of the product. Due to this protection group, the methyl group is oxidized during the second step, using potassium permanganate as the oxidizing agent, without destroying the amino functional group. This step converts a violet solution of permanganate ion to a brown manganese dioxide precipitate.