Advertisements
Advertisements
प्रश्न
Explain the term – rusting and give a word equation for the formation of rust. If polished iron nails are kept in three separate test tubes, state the contents in each test tube required, to prove the conditions for rusting.
उत्तर
The term Rusting involves slow oxidation of iron in presence of air and moisture which results in the formation of rust i.e. hydrated iron [III] oxide.
THE OXIDATION REACTION
Rusting of Iron
Iron + Oxygen → Iron [III] oxide Rust Hydrated iron [III] oxide
\[\ce{4Fe + 3O2 -> 2Fe2O3->[X H2O][moisture] Fe2O3.x H2O}\]
Iron when exposed to the atmosphere slowly reacts with the oxygen of the air, in the presence of moisture forming a brown coating called ‘rust’ on its surface. Rusting corrodes iron and reduces its structural strength.
APPEARS IN
संबंधित प्रश्न
Why do we apply paint on iron articles?
Two methods by which rusting of iron can be prevented are ______ and ______.
Explain why Iron sheets are coated with zinc during galvanization.
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
Name a common metal which is highly resistant to corrosion.
A metal X which is resistant to corrosion is produced by the electrolysis of its molten oxide whereas another metal Y which is also resistant to corrosion is produced by the reduction of its oxide with carbon. Metal X can be used in powder form in thermite welding whereas metal Y is used in making cathodes of ordinary dry cells.
(a) Name the metals X and Y.
(b) Which of the two metals is more reactive : X or Y?
(c) Name one ore or metal X. Also write its chemical formula.
(d) Name one ore or metal Y. Also write its chemical formula.
(e) Name one alloy of metal X and one alloy of metal Y.
Answer the following question:
What is corrosion? Do gold ornaments corrode? Justify.
Give reason.
An iron article should be given a coat of paint
Write scientific reason.
Coins are made from metals and alloys.
Observe the following diagram and give answers.
- Name this method of prevention of corrosion.
- For prevention of which metal this method is used?
- What is used as anode in this method?
