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प्रश्न
Write the name.
An alloy of copper and tin-
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उत्तर
An alloy of copper and tin- Bronze
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संबंधित प्रश्न
What is an alloy?
Write two methods of preventing the rusting of iron.
What are alloys?
Which of the following methods is suitable for preventing an iron frying pan from rusting?
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
State two conditions for the rusting of iron.
Fill in the following blank with suitable word:
The corrosion of iron is called ................
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.
Name two metals which resist corrosion due to the formation of a thin, hard and impervious layer of oxide on their surface.
What are the constituents of stainless steel?
Explain why, when a copper object remains in damp air for a considerable time, a green coating is formed on its surface. What is this process known as?
A common metal which is highly resistant to corrosion is:
(a) iron
(b) copper
(c) aluminium
(d) magnesium
Brass is an alloy of:
(a) Cu and Sn
(b) Cu and Pb
(c) Pb and Sn
(d) Zn and Cu
Mention two uses of the following metals and non-metals
Iron
Name the metal which is a constituent of blood pigment?
Compare roasting and calcination.
What are the adverse effects of corrosion?
Answer the following question:
What is corrosion? Do gold ornaments corrode? Justify.
Give a reason why rust turns moist red litmus blue.
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?
Which of the following method is used to prevent the accumulation of greenish layer on brass due to corrosion?
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.
Anodization method is useful for prevention of the corrosion of the aluminium.
Explain concept with example/explain with the help of a balanced equation.
Corrosion
Draw a neat labelled diagram.
Anodizing
Observe the following diagram and write answers.
- Name the method.
- Explain the method.
- Give two examples of this method.
The process of coating the surface of the metal with a thin layer of zinc is called ______
Give the equation for the formation of rust.
Galvanisation is a method of protecting iron from rusting by coating it with a thin layer of ____________.
Amalgam is an alloy of ____________.
Copper objects lose their shine and form green coating of ____________.
The diagram shows the reaction between metal and dil. acid.
What is the reason for different behaviour of Mg in test tube B?
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.
Describe two changes that are harmful. Explain why you consider them harmful. How can you prevent them?
