Which corrodes is faster?, Chemistry

Which of the following is corrodes faster?Iron pole in sea water or iton pole on the beach?

Ans) There are various ways of reducing and preventing this form of corrosion.

One way is to electrically insulate the two metals from each other. Until they are in electrical contact, there can be no galvanic couple set up. This can be completed using plastic or another insulator to separate steel water pipes from copper-based fittings or by using a coat of grease to divide aluminium and steel parts. Use of absorbent washers that may retain fluid is often counter-productive. Piping can be isolated with a spool of pipe made of plastic materials or made of metal material internally coated or lined. It is important that the spool has a minimum length of approx 500 mm to be effective.

One more way is to keep the metals dry or shielded from ionic compounds (salts, acids, bases), for example by painting or encasing the protected metal in plastic or epoxy, and permitted them to dry. Coating the two materials or if it is not possible to coat both, the coating shall be applied to the more noble, the material with higher potential. This is essential because if the coating is applied only on the more active material, in case of damage of the coating there will be a large cathode area and a very small anode area, and for the area effect the corrosion rate will be very high.

It is also possible to choose metals that have similar potentials. The more closely matched the individual potentials, the lesser the potential difference and therefore the lesser the galvanic current. Using the same metal for all construction is the most precise way of matching potentials. Electroplating or other plating can also help. This tends to use more noble metals that resist corrosion better. Chrome, nickel, silver and gold can all be used. Galvanizing with zinc protects the steel base metal by sacrificial action.

Posted Date: 3/11/2013 2:19:33 AM | Location : United States

Related Discussions:- Which corrodes is faster?, Assignment Help, Ask Question on Which corrodes is faster?, Get Answer, Expert's Help, Which corrodes is faster? Discussions

Write discussion on Which corrodes is faster?
Your posts are moderated
Related Questions
Semi-synthetic polymers Rayon and other cellulose derivatives such as cellulose nitrate, cellulose acetate so on, are semi-synthetic polymers. These illustrated as thermoplasti

How is harvest maturity identified? Before harvesting, the first thing to be looked into is the identification of harvest maturity. We have already seen what the term ac

Among the bonds formed by a chlorine atom with atoms of hydrogen, chlorine, sodium and carbon, the strongest bond is formed between (1) H- cl

If a mole were to have 1*10^24 particles what is the weight of one mole of oxygen molecule and 1 molecule of oxygen Ans) Since the gram molecular mass remains the similar...weig

Molten sodium chloride conducts electricity due to the presence of: (1) Free electrons (2) Free ions (3) Free molecules (4) Atoms of sodium and chlorine Ans:  Free

The Bohr orbit radius for the hydrogen atom (n=1)   is approximately  0.530 Å . The radius for the first excited state (n=2)  orbit is: (1) 0.13Å

Name the common element present in the anode mud in electro refinig of copper. Ans) ANTOMONY ,STRONSIUM,SELENIUM,TELLURIUM,SILVER,GOLD AND PLATINUM . THESE ELELMENTS ,BEING LESS R

Calculate the combustion energies for the burning of 1 mol of propane and butane. It can be supposed that all reactants and products are obtained under standard conditions.

What is the dipole moment of chloro-octane? Ans) There are many forms of the molecule "chloro-octane." This is due to the chlorine atom can be attached to the octane chain in va