HOW TO SOLVE:  Valence Electrons & Core Electrons

QUESTION:

Write the electron configuration for Ge. Identify the valence electrons and the core electrons

WORKED OUR SOLUTION & EXPLANATION:

To write the electron configuration for Germanium (Ge), which has an atomic number of 32, we need to distribute its electrons among the various atomic orbitals in the order of their increasing energy levels.

The electron configuration is built up following the Aufbau principle, Pauli exclusion principle, and Hund's rule. The Aufbau principle dictates the order in which orbitals are filled, the Pauli exclusion principle states that no two electrons in an atom can have the same set of four quantum numbers, and Hund's rule tells us that electrons will singly occupy degenerate orbitals before pairing up.

Germanium's electron configuration can be written as follows:

• The first two electrons fill the 1s orbital: 1s²

• The next two electrons fill the 2s orbital: 2s²

• The next six electrons fill the 2p orbitals: 2p⁶

• The next two electrons go into the 3s orbital: 3s²

• The next six electrons fill the 3p orbitals: 3p⁶

• The next ten electrons fill the 3d orbitals: 3d¹⁰

• The next two electrons go into the 4s orbital: 4s²

• The next six electrons fill the 4p orbitals, and since Ge has 32 electrons, the last two electrons will go into the 4p orbital: 4p²

So, the electron configuration of Ge is:

1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p²

Now, let's identify the valence and core electrons:

• Valence electrons are the electrons in the outermost shell of an atom. In the case of Ge, these are the electrons in the fourth shell (4s² 4p²), which amount to 4 electrons.

• Core electrons are all the other electrons that are not valence electrons. For Ge, these are the electrons in the 1s, 2s, 2p, 3s, 3p, and 3d orbitals, which add up to 28 electrons.

Therefore, Germanium has 4 valence electrons and 28 core electrons.