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प्रश्न
Find the odd one out and give its explanation.
विकल्प
Na
K
Cu
Li
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उत्तर
Cu
Explanation-
Copper (Cu) is a less reactive metal while others are highly reactive metals.
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संबंधित प्रश्न
Metallic oxides of zinc, magnesium and copper were heated with the following metals.
| Metal | Zinc | Magnesium | Copper |
| Zinc oxide | – | – | – |
| Magnesium oxide | – | – | – |
| Copper oxide | – | – | – |
In which cases will you find displacement reactions taking place?
A man went door to door posing as a goldsmith. He promised to bring back the glitter of old and dull gold ornaments. An unsuspecting lady gave a set of gold bangles to him which he dipped in a particular solution. The bangles sparkled like new but their weight was reduced drastically. The lady was upset, but after a futile argument, the man beat a hasty retreat. Can you play the detective to find out the nature of the solution he had used?
Name one metal which is extracted by reduction with heat alone.
A metal which exists as a liquid at room temperature is obtained by heating its sulphide ore in the presence of air.
(a) Name the metal and write its chemical symbol.
(b) Write the name and formula of the sulphide ore.
(c) Give the equations of chemical reactions involved in the production of metal from its sulphide ore.
(d) Name a common device in which this metal is used.
(e) Can this metal displace copper from copper sulphate solution? Why?
Give reasons, why aluminum is used in:
In making ships
Aluminum is used in thermite welding:
what is thermit?
Explain the following:
Galvanization protects iron from rusting.
Name the following:
The process of heating an ore to a high temperature in the presence of air.
Which one of the following is not true of metal :
Metals form non-polar covalent compounds
Which one of the following is not true of metal :
Metal will have 1 or 2 or 3 electrons in their valence shell.
Choose the correct answer from the options given below:
The metal is a liquid at room temperature.
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 ______.
Usually ______ ores are subjected to ______ which is done in the absence of air.
Write the name.
The process of strong heating of carbonate ores in insufficient air–
In the electrolytic method, a layer of highly active metal is applied to a less active metal.
Explain the following reaction with the balanced equation.
Zinc carbonate is heated strongly in limited supply of air
Explain in brief types of extraction of less reactive metals according to their reactivity.
In thermite welding a mixture of ____________ is ignited with a burning magnesium ribbon which produces molten iron metal as a large amount of heat is evolved.
Which of the following metals exist in their native state in nature?
- Cu
- Au
- Zn
- Ag
Care must be taken while diluting concentrated nitric acid with water. Why?
