In the electron configuration [ar]4s23d104p4, which are valence electrons?

The valence electrons are the one in the subshells 4s and 4p.

Explanation:

Let's consider the following electron configuration.

[Ar] 4s² 3d¹⁰ 4p⁴

The valence electrons are the ones in the last level, that is, the level 4. Here, there are two electrons in the s subshell and four electrons in the p subshell. In total, there are 2 + 4 = 6 valence electrons.

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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