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What can increase the voltage difference between a metal electrode and a solution?
Liliroc
If electrons are left behind in metal this will increase the voltage difference between a metal electrode and a solution. Also if the solution becomes more positive this will cause an increase.
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∙ 9y ago
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What is resistance of earthing electrode?
It's convenient to think of the earth electrode as being surrounded by a series of increasingly-larger 'shells' of soil, through which any earth-fault current will radiate outwards. The resistance of each 'shell' is inversely-proportional to its cross-sectional area. The shell immediately surrounding the earth electrode (1, in the following diagram) will have the smallest cross-sectional area and, therefore, the greatest resistance value; as we more further and further away from the earth electrode, each subseqent shell (2, 3, 4, etc.) increases in cross-sectional area and, therefore, reduces in resistance.The further we move away from the earth electrode, the difference between the size of each shell becomes less and less significant and, therefore, the resistance between adjacent 'shells', will become less and less until, eventually, the increase in resistance, too, will become negligible.The resistance of each of these 'shells' is, of course, cumulative. So, while the rate of change in resistance is greatest in the area immediately surrounding the earth electrode, the cumulative resistancecontinues to increase until it eventually become more-or-less constant. And it is this constant value that is taken as being the resistance of the earth electrode.In practice, we cannot use an ordinary ohmmeter to measure the resistance of the earth electrode. Instead, the basis of the test is actually as follows.A small spike is laid out in a straight line radiating away from the earth electrode. The resistance is then measured between the earth electrode and the spike, using an earth megger. The test is repeated several times, with the spike moved further and further away from the earth electrode. A graph drawn from the results shows a curve which is steepest (representing the greatest rate of change of resistance) where the test spike is closest to the earth electrode, and which eventually becomes horizontal (no further rate of change of resistance). The cumulative resistance increases, until there is no further significant increase in resistance, and this value is taken as the earth-electrode's resistance. The same results will be seen in whichever radial direction the resistance is measured, relative to the earth electrode. The area, immediately surrounding the earth electrode, in which the resistance value changes is termed its 'resistance area'.For the UK, the wiring regulations, BS 7671:2008, specifies that the value of the earth-electrode resistance must be 'low enough to ensure that the potential of any exposed metalwork, with respect to earth, during an earth fault does not exceed 50 V for normal, dry, conditions'.The 'On-Site Guide', a supplement to BS 7671:2008, further specifies (section 10.3.5) that the earth-electrode resistance should 'in any event, not exceed 200 Ω'.
What is manual arc welding?
Everybody used to call it "stick welding". MMAW Manual Metal Arc Welding is the correct nomenclature. The "sticks" are electrodes held in an electrode holder connected to a power supply. Establish an arc between the end of the electrode and the metal and move across the joint. As you weld the electrode is consumed. Discard the "stub", insert a new electrode and continue.
What is the difference between agitator and homogenizer?
agitator is a stirring machine, a homogenizer is a device that breaks structure in order to make a homogenious solution
What is redox mediator?
A redox mediator is a hyperbranched polymer having redox moieties (e.g. ferrocene) incorporated into its structure and/or chemically bonded to its periphery. It is attached to an electrode and assists in transferring electrons between the electrode and a redox enzyme.
What is the difference between pipe earthing and plate earthing?
Assuming your reference to "earthing" is grounding (Grounding Electrode Conductor), a pipe is, as it sounds, a pipe (i.e. water pipe). A plate would be, as it sounds, a square (or rectangular) copper plate which would be buried in the ground.
What is difference between standard hydrogen electrode and normal hydrogen electrode?
E(SCE)-E(H)=241 mV @25°C SHE is a primary standard electrode bt SCE is secondary reference electrode use for more easier work than SHE & SCE,s potential also measured by taking SHE as reference electrode.
What type of electrodes are used in potentiometric titration?
Potentiometric titration is a method to detect potential difference between the indicator electrode and reference electrode and thus determine concentration of chemical component, which reacts with reagent added to a solution potentially in equilibrium at the beginning.The popularly used reference electrode is either silver-silver chloride or mercury sulfate electrode, and the indicator electrode is generally made of glass electrode, platinum electrode and silver electrode or ion selective electrode.
Difference between reference electrode and indicator electrode?
Often electrochemical studies are interested in one of the electrodes of the cell only. The second electrode is present to complete the cell. Electrode of interest is named working electrode or the indicator electrode; the second electrode is know as reference electrode or auxiliary electrode (counter electrode).
What is the difference between mono polar and bipolar electrode?
Monopolar electrode is single electrode measure voltage with respect to grond ,but bipolar electrode is two electrode measures the diff. voltage mainly bipolar is used inorder to get high Signal to Noise ratio.
What is the difference between normal saline solution and ringer's lactate solution?
What is the difference between normal saline solution and ringer's lactate solution?
What is the difference between a simple solution and dilute solution?
Any difference exist. A simple solution may be a diluted solution.
What is a the major difference between a solution and an ordinary mixture?
The major difference between a solution and an ordinary mixture is that solution is homogeneous and an ordinary mixture is heterogeneous.
What is the difference between a molar solution and a normal solution?
kuta
What is the difference between algebraic solution and graphical solution to an equation?
whats the difference between solving an inequality by algebriac vs graphical
What is the difference between feasible and optimal solution?
The optimal solution is the best feasible solution
What is the basic technique or basic principle of amperometric titration?
The potential applied between the indicator electrode and the reference electrode is kept constant and the current through the electrolyte cell is then measured on addition of each increament oftitrating solution.
Difference between an increase in Supply and an increase in quantity supplied?
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