Advertisements
Advertisements
प्रश्न
Explain the terms Corrosion
Explain the term "corrosion" with an example.
Advertisements
उत्तर १
Corrosion is defined as a process where materials, usually metals, deteriorate as a result of a chemical reaction with air, moisture, chemicals, etc. For example, in the presence of moisture, iron reacts with oxygen to form hydrated iron oxide.
\[\ce{4Fe + 3O2 + H2O → 2Fe2O3.nH2O}\]
उत्तर २
Corrosion is a process where a refined metal is oxidised by atmospheric oxygen to form a more stable compound, such as oxides. The metal gradually degrades during the corrosion process. Iron rusting is a good example of corrosion, where the iron is converted to iron oxide. Millions of dollars are spent annually to prevent rusting on bridges and other monuments.
उत्तर ३
Corrosion is the process by which metal corrodes when it comes into contact with its surroundings, such as moisture, air, and acids. For example, a powdered (brown) coating on iron objects such as iron railings.
APPEARS IN
संबंधित प्रश्न
Tinning : Tin : : Galvanizing : _________
Which metals do not corrode easily?
Choose the correct answer from the options given below:
Heating an ore in a limited supply of air or in the absence of air at a temperature just below its melting point is known as
A. Smelting
B. Ore-dressing
C. Calcination
D. Bessemerisation
Write a chemical equation to show the process of corrosion of iron.
Name the metal which is used for galvanising iron.
Explain why, iron sheets are coated with zinc.
Fill in the following blank with suitable word:
The corrosion of iron is called ................
Fill in the following blank with suitable word:
The corrosion of copper produces a .............. coating of basic copper carbonate on its surface
Name two metals which resist corrosion due to the formation of a thin, hard and impervious layer of oxide on their surface.
No chemical reaction takes place when granules of a rusty-brown solid A are mixed with the powder of another solid B. However, when the mixture is heated, a reaction takes place between its components. One of the products C is a metal and settles down in the molten state while the other product D floats over it. It was observed that the reaction is highly exothermic.
(a) What could the solids A and B be?
(b) What are the products C and D most likely to be?
(c) Write the chemical equation for the reaction between A and B leading to the formation of C and D. Mention the physical states of all the reactants and products in this equation and indicate the heat change which takes place.
(d) What is the special name of such a reaction? State one use of such a reaction.
(e) Name any two types of chemical reactions under which the above reaction can be classified.
Explain with reason:
Roasting is carried out on sulphide ores and not on carbonate ores.
No chemical reaction takes place when granules of a solid, A, are mixed with the powder of another solid, B. However when the mixture is heated, a reaction takes place between its components. One of the products, C, is a metal and settles down in the molten state while the other product, D, floats over it. It was observed that the reaction is highly exothermic.
(i) Based on the given information make an assumption about A and B and write a chemical equation for the chemical reaction indicating the conditions of reaction, physical state of reactants and products and thermal status of reaction.
(ii) Mention any two types of reactions under which above chemical reaction can be classified.
To prevent corrosion of iron and steel _______ method is used.
Complete flow chart given below.
Identify the correct statement from the following:
Generally, when metals are treated with mineral acids, hydrogen gas is liberated but when metals (except Mn and Mg), treated with HNO3, hydrogen is not liberated, why?
A man painted his main gate made up of iron, to
- prevent it from rusting.
- protect it from sun.
- make it look beautiful.
- make it dust free.
Which of the above statement(s) is/are correct?
Galvanisation is a process used to prevent the rusting of which of the following?
Give an example of a chemical reaction for the following situation:
Sound is produced
Explain the chemical reactions in rusting of iron.
