Electric current electrolysis

Electrochemistry — Electrochemistry, as the name suggests, is a branch of chemical science that deals with the interrelation of electrical and chemical phenomena [i]. From the very beginning electrochemistry covers two main areas the conversion of the energy of chemical reactions into electricity (electrochemical power sources) and the transformations of chemical compounds by the passage of an electric current (-> electrolysis). 

A 100.0-g sample of water was decomposed using an electric current (electrolysis) producing hydrogen gas and oxygen gas. Write the balanced equation for the process and calculate the volume of each gas produced (STP). Explain any relationship you may observe between the volumes obtained and the balanced equation for the process. 

Notice how many kinds of chemical reactions are organized into the production of magnesium—decomposition by heat, neutralization, precipitation, and oxidation-reduction by using electrical current (electrolysis). 

The electrolyte thus formed can conduct electric current by the movement of ions under the influence of an electric field. A cell using an electrolyte as a conductor and a positive and a negative electrode is called an electrolysis cell. If a direct-current voltage is appHed to a cell having inert electrode material such as platinum, the hydrogen ions (cations) migrate to the cathode where they first accept an electron and then form molecular hydrogen. The ions... 

Faraday s Law of electrolysis states that the amount of chemical change, ie, amount dissolved or deposited, produced by an electric current is proportional to the quantity of electricity passed, as measured in coulombs and that the amounts of different materials deposited or dissolved by the same quantity of electricity are proportional to their gram-equivalent weights (GEW) defined as the atomic weight divided by the valence. The weight in grams of material deposited, IF, is given by... 

The cell is the basis of all electrolysis. The anode admits current into the electrolyte and the cathode serves as a means of exit for the electrical current. The electrical flow provides a definition for electrolysis the flow of current from the anode through the electrolyte and out of the cell through the cathode with ensuing decomposition of the electrolyte, with products being formed at the electrodes. 

Current density can be increased without impairing the quaUty of the copper by polishing the cathode surface by brief periodic current reversals (PCR). Reversed current electrolysis, first developed for electroplating, was tested in 1952 for copper refining. Although good results were obtained, no suitable electrical equipment for current reversal was available. The thyristor-controUed siUcon rectifier, introduced in the 1960s, provided a means for... 

Electric current passing through a metal joint having a moisture content causes electrolysis of water vapour. Copper, being a galvanic metal, forms an electrolytic circuit with other metals and decomposes the joint. Decomposition is corroding and erodes the aluminium metal. 

Some years after Davy s death, Faraday examined the corrosion of cast iron in sea water and found that it corrodes faster near the water surface than deeper down. In 1834 he discovered the quantitative connection between corrosion weight loss and electric current. With this discovery he laid the scientific foundation of electrolysis and the principles of cathodic protection. 

Stray current corrosion is an electrolytic degradation of a metal caused by unintentional electrical currents. Bad grounds are the most prevalent causes. The corrosion is actually a typical electrolysis reaction. 

Electrolysis-a reaction in which chemical change results in an electrolyte being produced from the passage of electric current. 

So far in this chapter we have dealt with reactions that proceed spontaneously. But the same ideas and names are applied to reactions that we force to take place, against their natural tendency, by supplying energy with an externally applied electric current. Such a process is termed electrolysis or separation by electricity. ... 

Electric current, 78 Electric dipoles, see Dipoles Electric discharge, 239 Electric force, 76, 77 Electricity, fundamental unit, 241 Electrochemical cell chemistry of, 199 and Le Chatelier s Principle. 214 operation, 206 standard half cell, 21C Electrodes, 207 Electrolysis, 220, 221 apparatus, 40 cells, 238 of water, 40, 115 Electrolytes, 169, 179 strong, 180 weak,180... 

In this part of Chapter 12, we study electrolysis, the process of driving a reaction in a nonspontaneous direction by using an electric current. First, we see how electrochemical cells are constructed for electrolysis and how to predict the potential needed to bring electrolysis about. Then, we examine the products of electrolysis and see how to predict the amount of products to expect for a given flow ot electric current. 

When carrying out an electrolysis in solution, we must consider the possibility that other species present might be oxidized or reduced by the electric current. For example, suppose that we want to electrolyze water to produce hydrogen and oxygen. Because pure water does not carry a current, we must add an ionic solute with ions that are less easily oxidized or reduced than water ... 

Faraday s law of electrolysis The amount of product formed or reactant consumed by an electric current is stoichiometrically equivalent to the amount of electrons supplied. 

Emission of li t accompanying the passage of an electric current through aqueous solutions and arising from chemical reactions of chemiluminescent species produced during electrolysis. 

Manufacture Co-produced with sodium hydroxide by the electrolysis of salt brine. electrical current 2NaCH-2H20 2NaOH -1- H2 -l- CI2 sodium water hydrogen chlorine chloride... 

H3 0 (a g) + CrO ia ij) + 6 e -> Cr(. ) + 12 H2 0(/) This reaction proceeds much faster than the direct reduction of Cr . It requires twice as much electrical current, however, since 6 mol of electrons must be supplied to deposit 1 mol of Cr rather than 3 mol for direct electrolysis of. ... 

Of all electrical phenomena electrolysis appears the most likely to furnish us with a real insight into the true nature of the electric current, because we find currents of ordinary matter and currents of electricity forming essential parts of the same phenomenon. 

One suggested application of solar energy is to use the electrical current that can be generated for the electrolysis of water. What product of the electrolysis would be most valuable as an energy source Explain your choice. 

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