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प्रश्न
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 |
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उत्तर
| Group A | Group B |
| 1) Electroplating | b) Silver plated spoons |
| 2) Anodising | a) Pressure cooker |
APPEARS IN
संबंधित प्रश्न
What is an alloy?
Tinning : Tin : : Galvanizing : _________
Write two methods of preventing the rusting of iron.
Give reasons:
Platinum, gold and silver are used to make jewellery.
Two methods by which rusting of iron can be prevented are ______ and ______.
In one method of rust prevention, the iron is not coated with anything. Which is this method?
Fill in the following blank with suitable word:
The corrosion of copper produces a .............. coating of basic copper carbonate on its surface
Give the constituents and one use of brass.
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
Bronze is an alloy of ______.
Name the metal which is a constituent of plant pigment?
No chemical reaction takes place when granules of a 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.
(i) Based on the given information make an assumption about A and B and write a chemical equation for the chemical reaction indicating the conditions of reaction, physical state of reactants and products and thermal status of reaction.
(ii) Mention any two types of reactions under which above chemical reaction can be classified.
Observe the following picture a write down the chemical reaction with the explanation.
Write scientific reasons.
Lemon or tamarind is used for cleaning copper vessels turned greenish.
Find the odd man out:
What is done to prevent corrosion of metals?
Write three methods of preventing rusting of iron.
Give reason.
An iron article should be given a coat of paint
Give a reason why rust turns moist red litmus blue.
State whether the statement given below is true or false. If false write the correct statement.
Either oxygen or moisture is essential for rusting.
Rusting of iron : Fe2O3 : : corrosion of copper : ______
Find the odd one out and give its explanation.
Find the odd one out and give its explanation.
Write the name.
Method used to prevent corrosion of copper.
Write scientific reason.
On exposure to air, silver articles turn blackish after some time.
Draw a neat labelled diagram.
Anodizing
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?
Observe the following figure and write the answer of the question.
- Which process is shown in the figure?
- Explain the chemical reaction shown in the figure.
- Write the reactions on anode and cathode.
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.
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:
Galvanisation is a process used to prevent the rusting of which of the following?
State whether the following statement is true or false:
Ships suffer a lot of damage though they are painted.
Gold plated ornaments is the example of ______.
Give scientific reasons.
Silver amalgam is used for filling dental cavities.
