How many valence electrons are in a neutral lithium atom?

how many valence electrons are in a neutral lithium atom?

How many valence electrons are in a neutral lithium atom?

Answer:

Valence electrons are the electrons in the outermost shell of an atom that are involved in chemical bonding. To determine the number of valence electrons in a neutral lithium atom, we need to look at its electron configuration.

Electron Configuration of Lithium

  1. Atomic Number of Lithium:

    • A neutral lithium atom has an atomic number of 3, which means it has 3 protons and, correspondingly, 3 electrons.
  2. Electron Configuration:

    • The electron configuration of lithium follows the order of filling of atomic orbitals. The configuration is given by distributing the electrons in the increasing order of energy levels.

      For lithium:

      • The first two electrons fill the 1s orbital.
      • The third electron goes into the next available orbital, which is the 2s orbital.

      Thus, the electron configuration for lithium can be written as:

      1s^2 2s^1
  3. Valence Electrons:

    • Valence electrons are located in the outermost shell of the atom. For lithium, the outermost shell is the 2s orbital which contains 1 electron.

Conclusion:

Therefore, a neutral lithium atom has 1 valence electron.


By understanding the concept of electron configuration, one can systematically determine the number of valence electrons present in any atom. For lithium:

  • The electron configuration is 1s^2 2s^1.
  • The single electron in the 2s orbital is the valence electron.

Final Answer:
A neutral lithium atom has 1 valence electron.