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प्रश्न
What is rust?
उत्तर
A certain type of reddish coloured solid layer collects on iron surface. This layer is called ‘rust’.
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संबंधित प्रश्न
What is an alloy?
Write two methods of preventing the rusting of iron.
What special name is given to their corrosion of iron?
Fill in the following blank with suitable word:
The process of depositing a thin layer of zinc on iron articles is called .............
Fill in the following blank with suitable word:
The corrosion of copper produces a .............. coating of basic copper carbonate on its surface
Explain why, through aluminium is more reactive than iron, yet there is less corrosion of aluminium when both are exposed to air.
Name any two metals which do not corrode easily.
What is meant by 'rusting of iron'? With the help of labelled diagrams, describe an activity to find out the conditions under which iron rusts.
Give the constituents and one use of brass.
What are the constituents of stainless steel?
A common metal which is highly resistant to corrosion is:
(a) iron
(b) copper
(c) aluminium
(d) magnesium
Mention two uses of the following metals and non-metals
Iron
Bronze is an alloy of ______.
What is corrosion? What are necessary conditions for corrosion?
State under what conditions corrosion is faster ?
Compare roasting and calcination.
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 ..................................................................
What are the adverse effects of corrosion?
Choose the correct alternative and rewrite the following:
Iron is _____________________.
Answer the following question:
What is corrosion? Do gold ornaments corrode? Justify.
Give reason.
An iron article should be given a coat of paint
Give reason.
Copper and brass utensils should be tinned.
Observe the following picture and answer the following questions:
- What is rust?
- Write the chemical formula of rust.
- Write the reaction of oxidation of iron at the anode.
- Write the reaction of oxidation of iron at the cathode.
- What is corrosion?
Corrosion of silver causes a black layer of _______.
Stainless steel is an alloy of _______.
Find the odd one out and give its explanation.
Find the odd one out and give its explanation.
Write the name.
An alloy of copper and tin-
Write the name.
Method used to prevent corrosion of copper.
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?
The iron pillar near the Qutub Minar in Delhi is famous for the following facts. Which of these facts is responsible for its long stability?
State whether the following statements are true or false:
Ships suffer a lot of damage though they are painted.
Explain the following:
Lime water turns milky on passing carbon dioxide gas into it.
Explain the following:
Bubbles are produced when acetic acid is added to a solution of sodium hydrogencarbonate.
In ______ process a layer of molten tin is deposited on metals.
