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प्रश्न
To prevent corrosion of iron and steel _______ method is used.
पर्याय
electroplating
anodization
tinning
galvanizing
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उत्तर
To prevent corrosion of iron and steel galvanizing method is used.
APPEARS IN
संबंधित प्रश्न
Explain the term corrosion.
Two methods by which rusting of iron can be prevented are ______ and ______.
What special name is given to the corrosion of iron?
Name any three objects (or structures) which are gradually damaged by the corrosion of iron and steel.
The chemical reaction involved in the corrosion of iron metal is that of ______.
What is meant by galvanisation? Why is it done?
Explain why, iron sheets are coated with zinc.
Fill in the following blanks with suitable words:
............ and .............. are necessary for the rusting of iron.
Name two metals which resist corrosion due to the formation of a thin, hard and impervious layer of oxide on their surface.
Name an alloy of copper. State its chemical composition and any one use.
Explain why, when a copper object remains in damp air for a considerable time, a green coating is formed on its surface. What is this process known as?
Name a common metal which is highly resistant to corrosion.
A common metal which is highly resistant to corrosion is:
(a) iron
(b) copper
(c) aluminium
(d) magnesium
In stainless steel alloy, iron metal is mixed with:
(a) Cu and Cr
(b) Cr and Ni
(c) Cr and Sn
(d) Cu and Ni
If copper is kept exposed to damp air for a considerable time, it gets a green coating on its surface. This is due to the formation of:
(a) hydrated copper sulphate
(b) copper oxide
(c) basic copper carbonate
(d) copper nitrate
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 how the activity series accounts for each of the following:
tendency to corrosion
Explain with reason:
Roasting is carried out on sulphide ores and not on carbonate ores.
Observe the following picture a write down the chemical reaction with the explanation.
Complete the process of iron rusting by filling the blanks. Suggest a way to prohibit the process.
The iron rust is formed due to........................... reaction. Different
regions on iron surface become anode and cathode.
Reaction on anode region :
`F_e(s) → Fe^(2+) (aq) +2e^-`
Reaction on anode region :
`O_2(g) + 4H^+(aq) +............................ → 2H_2 O (l) `
When Fe2+ ions migrate from anode region they react with ................... to form Fe3+ ions.
A reddish coloured hydrated oxide is formed from ............... ions. It is called rust.
`2Fe_(3+) (aq) + 4H_2O(l) → ................. + 6H_+(aq) `
A way to prevent rusting ..................................................................
Answer the following question.
a) What is meant by corrosion?
b) Write names of any two methods of prevention of corrosion.
c) In which method, metal like copper, aluminium are coated with a thin layer of their oxides by means of electrolysis.
d) Explain this method with diagram.
Answer the following question:
What is corrosion? Do gold ornaments corrode? Justify.
Write three methods of preventing rusting of iron.
Give reason.
An iron article should be given a coat of paint
Give reason.
Copper and brass utensils should be tinned.
Give a reason why rust turns moist red litmus blue.
Bronze : _______ : : Stainless steel : Fe + Cr + C
Give preventive methods by giving examples of corrosion?
The process of coating the surface of the metal with a thin layer of zinc is called ______
Galvanisation is a method of protecting iron from rusting by coating it with a thin layer of ____________.
Which among the following alloys contain mercury as one of its constituents?
Marble’s popularity began in ancient Rome and Greece, where white and off-white marble were used to construct a variety of structures, from hand-held sculptures to massive pillars and buildings.
The substance not likely to contain CaCO3 is:
Identify the correct statement from the following:
Iron pillar near the Qutub Minar in Delhi is famous for the following facts. Which of these facts is responsible for its long stability?
Gold plated ornaments is the example of ______.
Describe two changes that are harmful. Explain why you consider them harmful. How can you prevent them?
