Which element has the following complete electron configuration : 1s22s22p63s23p64s23d5?

Manganese

Explanation:

The electronic configuration of the atom is:

         1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁵

The powers in this configuration is the number of electrons in each orbital:

2 + 2 + 6 + 2 + 6 + 2 + 5  = 25

The compound has 25 electrons and it is Manganese

oxygen, selenium, tellurium, and polonium.

they're all from the same group as sulfur (group 16).

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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