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प्रश्न
Observe the following diagram and write answers.
- Name the method.
- Explain the method.
- Give two examples of this method.
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उत्तर
- The method is called electroplating.
- Explanation:
a. Electroplating is the process in which a less reactive metal is coated on a more reactive metal by electrolysis.
b. It protects the object made of reactive metal from corrosion. c. It also improves the appearance of the object. - Silver plated spoons, gold plated ornaments are examples of electroplating.
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संबंधित प्रश्न
What is an alloy?
Write two methods of preventing the rusting of iron.
Why do we apply paint on iron articles?
Explain the term corrosion.
Which metals do not corrode easily?
What are alloys?
What is anodising? Give its applications.
What type of chemical reaction is involved in the corrosion of iron?
In one method of rust prevention, the iron is not coated with anything. Which is this method?
Why is an iron grill painted frequently?
Explain why, though aluminium is more reactive than iron, yet there is less corrosion of aluminium when both are exposed to air.
Give the constituents of brass.
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.
Brass is an alloy of ______.
Name the metal which is a constituent of blood pigment?
Corrosion can be an advantage in some case.Explain ?
Compare roasting and calcination.
Observe the following picture a write down the chemical reaction with the explanation.
What is done to prevent corrosion of metals?
What is ‘rusting’?
Give a reason why rust turns moist red litmus blue.
To prevent corrosion of iron and steel _______ method is used.
When one of the metals in an alloy is mercury the alloy is called _______.
Find the odd one out and give its explanation.
Find the odd one out and give its explanation.
Write scientific reason.
On exposure to air, silver articles turn blackish after some time.
Explain concept with example/explain with the help of a balanced equation.
Corrosion
Draw a neat labelled diagram.
Anodizing
Give solutions by giving examples of corrosion?
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.
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?
Galvanisation is a process used to prevent the rusting of which of the following?
Describe two changes that are harmful. Explain why you consider them harmful. How can you prevent them?
