Metals are good conductors of electricity because – (1) they contain free electrons (2) the atoms are lightly packed (3) they have high melting point (4) All of the above

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Answer :

(1) they contain free electrons Explanation: Copper is used for electrical wiring because it is a good conductor of electricity. Metal particles are held together by strong metallic bonds, which is why they have high melting and boiling points.

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Description : Metals are good conductors of electricity because - (1) they contain free electrons (2) the atoms are lightly packed (3) they have high melting point (4) All of the above

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Last Answer : Ans:(b)

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Last Answer : (c) Large number of free electrons

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Last Answer : they contain free electrons

Description : (a) If the radius of the Br ion is 0.182 nm, how large a cation can fit in each of the tetrahedral hole. (b) AgI crystallizes in a cubic closed packed ZnS structure. What fraction of tetrahedral site ... Ag ion ?  (c) At what temp. range, most of the metals becomes super conductors ?

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Last Answer : (c) Similar charges repel each other

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Description : On a cold day when the room temperature is 15°C, the metallic cap of a pen becomes much colder than its plastic body, though both are at the same temperature of 15°C, because - (1) metals ... metals (3) metals are good conductors of heat (4) plastics have a higher thermal conductivity than metals

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Description : Atoms with four valence electrons are good conductors. (A) True (B) False

Last Answer : (B) False

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Description : Which of the following is false? (1) Most carbon compounds are poor conductors of electricity. (2) The force of attraction between carbon molecules is not very strong. (3) The atomic number of carbon is 6. (4) The earth’s crust has about 2% carbon in the form of minerals.

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Description : Method of separating metals which have low melting point I from an ore is?

Last Answer : Liquation

Description : Give reason .the melting point and boiling point of alkali metals are low 

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Description : Give reason for the higher melting point and boiling point of alkali earth metals than alkali metals. 

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Description : Which of the following metals has least melting point ? (1) Gold (2) Silver (3) Mercury (4) Copper

Last Answer : Mercury

Description : Which one of the following non-metals is not a poor conductor of electricity? (1) Sulphur (2) Selenium (3) Bromine (4) Phosphorus

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