Electron Chemistry Example 3

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Example 3

easy
How many electrons does a neutral atom of magnesium (Z=12Z = 12) have? Write its electron configuration.

Solution

  1. 1
    Neutral atoms have electrons equal to protons, so Mg has 12 electrons.
  2. 2
    Configuration: 1s2 2s2 2p6 3s21s^2\,2s^2\,2p^6\,3s^2.

Answer

1s2 2s2 2p6 3s21s^2\,2s^2\,2p^6\,3s^2
Follow the Aufbau principle: fill 1s1s, then 2s2s, then 2p2p, then 3s3s.

About Electron

A negatively charged subatomic particle with negligible mass that occupies energy levels (shells) outside the nucleus.

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More Electron Examples

Example 1 easy

Write the electron configuration for oxygen ([formula]).

Example 2 medium

A chlorine atom ([formula]) gains one electron. Write the electron configuration of the resulting [f

Example 4 medium

Which subatomic particle is mainly responsible for chemical bonding, and why?

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