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प्रश्न
Write three methods of preventing rusting of iron.
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उत्तर
Three methods of preventing rusting of iron:
A. Galvanizing: It is a process of giving a thin coating of zinc on iron or steel to protect them from corrosion, E.g. shiny iron nails. pins etc.
B. Rusting of iron can be prevented by coating it with paint, oil, grease or varnish.
C. Tinning: In this process thin layer of tin is coated over iron objects.
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संबंधित प्रश्न
What is an alloy?
Give two examples of alloys with their chemical composition.
What are alloys?
Explain why, iron sheets are coated with zinc.
______ and ______ are necessary for the rusting of iron.
With the help of labelled diagrams, describe an activity to find out the conditions under which iron rusts.
Name five methods of preventing rusting of iron.
Bronze is an alloy of ______.
Explain with reason:
Roasting is carried out on sulphide ores and not on carbonate ores.
Write scientific reasons.
Lemon or tamarind is used for cleaning copper vessels turned greenish.
Answer the following question:
What is corrosion? Do gold ornaments corrode? Justify.
Answer the following question.
List two properties of alloys.
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 _______.
Match the columns.
| Group A | Group B |
| 1) Electroplating | a) Pressure cooker |
| 2) Anodising | b) Silver plated spoons |
| c) Coating of tin on copper | |
| d) Coating of Zinc on iron |
What is rust?
State two conditions necessary for rusting of iron.
The table shown below gives information about four substances: A, B, C and D.
| SUBSTANCE | MELTING POINT (K) | ELECTRICAL CONDUCTIVITY | |
| SOLID | LIQUID/ AQUEOUS | ||
| A | 295 | Good | Good |
| B | 1210 | Poor | Good |
| C | 1890 | Poor | Good |
| D | 1160 | Poor | Poor |
Identify Ionic compounds from the above given substances.
Gold plated ornaments is the example of ______.
