3. An element reacts with oxygen to
give a compound with a high
melting point. This compound is
also soluble in water. The element
is likely to be
(b)
Metals
Non-metals
1. Metals are malleable.
1. Non metals are non-malleable(britle)
2. Metals are good conductors a of 2. Non-metals are poor or non
electricity
conductors of electricity.
3. Metals are sonorous.
3. Non metals are non-sonorous
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b) Lolcium bau bon vijnana Kirana
c) silicon aliton
Answers
Explanation:
NCERT IN-TEXT QUESTIONS SOLVED
1. Give an example of a metal which
(i) is a liquid at room temperature.
(ii) cart be easily cut with knife.
(iii) is the best conductor of heat.
(iv) is a poor conductor of heat.
Ans. (i) Mercury (Hg)
(ii) Sodium and potassium
(iii) Silver and copper
(iv) Lead -.
2. Explain the meanings of malleable and ductile.
Ans. Malleable: A metal is said to be malleable if it can be beaten into thin sheets, e.g. silver and gold are the best malleable metals.
Ductile: A metal is said to be ductile when it can be drawn into thin wires, e.g. silver and gold are the best ductile metals.
3. Why is sodium kept immersed in kerosene oil?
Ans. Sodium is highly reactive metal. It reacts with oxygen in air at room temperature, the reaction is highly exothermic. To prevent this sodium is kept preserved under kerosene. Sodium does not react with kerosene.
4. Write equations for the reactions of
(i) iron with steam
(ii) calcium and potassium with water
Ans. (i) Iron with