An introduction and application of the cyclic voltammetry Introduction When consider about the electroanalytical methods in analytical chemistry, there have a wide variety ways to think of. For example, there has a lot of voltammetry that can be considered in application such as cyclic voltammetry, square wave voltammetry, linear sweep voltammetry, staircase voltammetry. All these methods are widely used in several aspects of analytical ways in modern society. For example, by using the voltammetry can judge the electrode surface reaction process, the reversible or irreversible of the electrode reaction, the feature of the catalytic reaction of the cyclic voltammetry, and setting a condition for the organic synthesis. Also, the cyclic voltammetry is used the data of current and the potential to analysis. Therefore, using voltammetry methods is a common and useful ways nowadays. Method and set up Cyclic voltammetry are consist of three electrodes, which include the reference electrode, working electrode and the counter electrode, which the first figure is shown below. In order to get the conductivity, it is common to put the electrolyte to the test solution. The mixture of the electrolyte and the working electrode can make the value of the potential. It usually has the platinum or gold for the working electrode. Also, the working electrode may be have results when cyclic voltammetry have to run in high scan rates. For the auxiliary electrode, which is called counter electrode, can be conducted easily, ... ... middle of paper ... ...by the calibration curve through the current and the concentration in the Nernst system. Conclusion In modern society, there are several analytical methods to analysis the chemical compounds such as HPLC, GC, MS. However, for the redox reaction specifically, it is widely used through the electroanalytical methods which is cyclic voltammetry. It can be used in electrode absorption phenomenon, and electrochemical reaction products. It is commonly used in organic compounds and the biology materials mechanisms for the oxidation-reduction reaction research. Reference textbook ppt http://baike.baidu.com/view/921272.htm https://answers.yahoo.com/question/index?qid=20071116044700AAoXkt1 http://en.wikipedia.org/wiki/Cyclic_voltammetry
The purpose of this experiment was to examine how the stoichiometry, “the quantitative relationships between substances involved in a chemical reaction”, can be applied to determine the quantity of sodium hypochlorite found in a bleach product. This experiment allowed it to determine how much oxidizing agent is in a cleaner by using a redox reaction, which is a reaction involving the transfer of electrons from the compound being oxidized to the compound being reduced. To determine the amount of oxidizing agent, it is necessary to accurately measure out known amounts of redox reactants, know the stoichiometry
The basic principle of the spectrophotometeric technique is the measurement of interaction between energy and electrons of the substance. Spectrophotometric technique is an analytical method used for estimating concentration of metal ion in liquid solution. One of the most magnificent effects of complex formation is the change of spectral properties. The reason for light absorption by complexes are as follows.
In terms of kinetics, specifically speaking, the rate of reaction as determined by the concentration, reaction orders, and rate constant with each species in a chemical reaction. By using the concentration of the catalyst and the temperature, the overall reaction rate was determined. The rate constants of K0, Kobs, and Kcat can be derived via the plotting of the absorption at 400nm of p-nitrophenol vs. the concentration of the catalyst imidazole. Lastly, the free energy of activation, G, that is necessary to force the reactant’s transformation of the reactant to the transition state structure will be determined by using the equation G = H – TS derived from the Eyring plot. Introduction: The purpose of the experiment is to study the rate of reaction through varying concentrations of a catalyst or temperatures with a constant pH, and through the data obtained the rate law, constants, and activation energies can be experimentally determined.
During this time, it could only be used in a lab with semi-intense supervision. Now, fast forward a few decades and there are D.I.Y. at home kits. The process of Electrophoresis starts with an electric current being run through a gel containing the molecules of interest. The molecules will then travel through the gel in different directions and speeds, based on their size and charge, allowing them to be separated from each other. Dyes, fluorescent tags, and radioactive labels can all enable the molecules on the gel to be seen after they have been separated. Because of these identification markers, they appear as a band across the top of the gel. Electrophoresis can be used for many different things. It is used to identify and study DNA or DNA fragments, and helps us to better understand the molecular components of both living and deceased organisms. Electrophoresis can also be used to test for genes related to specific diseases and life altering diagnoses such as Multiple Sclerosis, Down’s Syndrome, kidney disease, and some types of cancer. Electrophoresis also plays a major role in the testing of antibiotics. It can be used to determine the purity and concentration of one specific type of antibiotic or several general antibiotics at a time. Electrophoresis is also extremely useful in the creation and testing of
The purpose of this lab was to to cycle solid copper through a series of chemical forms and return it to its original form. A specific quantity of copper undergo many types of reactions and went through its whole cycle, then returned to its solid copper to be weighted. We observed 5 chemical reactions involving copper which are: Redox reaction (which includes all chemical reactions in which atoms have their oxidation state changed), double displacement reaction, precipitation reaction, decomposition reaction, and single displacement reaction.
In the first part of this project, two cation elimination tests and one cation confirmation test were performed. 10 drops of 4 cation solutions: potassium, zinc(II), copper(II)
An electrode is a component of an electric circuit that connects the conventional wiring of the circuit to a conducting medium such as an electrolyte or a gas. The electrically positive electrode is called the anode and the negative electrode the cathode. If an anode and a cathode are placed in a solution of an electrolyte and a source of direct current is connected between them, the positive ions in the
Metals contain a sea of electrons (which are negatively charged) and which flow throughout the metal. This is what allows electric current to flow so well in all metals. An electrode is a component of an electric circuit that connects the wiring of the circuit to a gas or electrolyte. A compound that conducts in a solution is called an electrolyte. The electrically positive electrode is called the anode and the negative electrode the cathode.
Another widely used primary cell is the zinc-mercuric-oxide cell, more commonly called a mercury battery. It can be made in the shape of a small flat disk and is used in this form in hearing aids, and electric wristwatches. The negative electrode consists of zinc, the positive electrode is of mercuric oxide, and the electrolyte is a solution of potassium hydroxide. The mercury battery produces about 1.34 volts.
The Electrolysis of Copper Sulphate Aim Analyse and evaluate the quantity of Copper (Cu) metal deposited during the electrolysis of Copper Sulphate solution (CuSo4) using Copper electrodes, when certain variables were changed. Results Voltage across Concentration of solution electrode 0.5M 1.0M 2.0M 2 5.0 10.6 19.5 4 10.5 19.8 40.3 6 14.3 26.0 60.2 8 15.2 40.4 80.3 10 15.0 40.2 99.6 12 15.1 40.0 117.0 Analysing/Conclusion The input variables in this experiment are; concentration of the solution and the voltage across the electrodes. The outcome is the amount of copper gained (measured in grams) at the electrodes. By analyzing the graph, we can see the rapid increase of weight gained for the 2.0 molar concentration as the gradient is steeper.
LAB REPORT 1st Experiment done in class Introduction: Agarose gel electrophoresis separates molecules by their size, shape, and charge. Biomolecules such as DNA, RNA and proteins, are some examples. Buffered samples such as glycerol and glucose are loaded into a gel. An electrical current is placed across the gel.
A complexometric titration takes place in an aqueous sample inorder to displace water from the ion. As the metal ion will be ionated once in solution therefore, empty valence empty shells are achieved [1]
In recent years, electrochemical supercapacitors (ECs) have been extensively studied as attractive energy storage devices. They have potential applications in portable electronics and electric vehicles because of their high power energy densities and long cyclic life [8, 101, 102]. Based on the nature of the charge-storage mechanism and active materials, electrochemical capacitors can be classified into two types: electrochemical double layer capacitors (EDLCs) and redox supercapacitors (pseudocapacitors). EDLCs utilizing carbon-based active materials, such as activated carbon (AC) and carbon nanotubes (CNTs) with charge stored at electrode-electrolyte interface, are currently the most commonly used devices [2]. On the other hand, pseudocapacitors or redox capacitors use fast and reversible faradaic surface reactions for charge storage. Conducting polymers [103, 104] and transition metal oxides and hydroxides [81, 105, 106] have been investigated as possible electrode materials for redox capacitors. Redox capacitors have drawn much more attention than EDLCs due to their high theoreti...
Electrolysis Investigation Planning In this investigation, I will assess how changing the electric current in the electrolysis of acidified water affects the rate at which hydrogen gas is produced. The solution to be electrolysed is made up using acid and water. It is of little consequence what acid is used however in this case I will use Sulphuric acid (H2SO4). When H2SO4 is put in water it is dissociated and forms ions: H2SO4 → 2H (2+) + SO4 (2-) Ions are also present from the water in the solution: H2O → H (+) + OH (-) During the electrolysis process, the positive hydrogen ions move towards the cathode and the negative hydroxide and sulphate ions move towards the anode.
Electroplating Experiment Aim To find the amount copper gains or loses on the electrodes using different amounts of current each time during electrolysis. How the changing of current affects the electroplating of copper. Introduction Electroplating is generally carried out in order to improve the appearance or corrosion resistance of the surface of a metal by electrodepositing a thin layer of metal ion on it. The metal substrate to be coated is made by the cathode in an electrolytic cell. The cell used in electroplating contains an electrolyte which is usually an aqueous solution containing a reasonably high concentration of an ion of the metal which is to be electroplated on the surface.