Atoms are so small that approximately of them can fit at the end of a needle?

5 million million atoms can fit at the end of a needle

Let's just say 5 million million hydrogen atoms could fit at the end of a needle.

Explanation:

Atoms are 100 picometers, and to compare, the amount of even 1 centimeter, a calculator can't even figure out how many picometers are in a centimeter because there is just too much picometers.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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