What for does KK stand in the molecular orbital electronic configuration KK `( sigma _(2s))^2 ` for `Li_2` molecule?

Explanation

To understand what "KK" stands for in the molecular orbital electronic configuration \( KK \sigma_{2s}^2 \) for the \( Li_2 \) molecule, we can break down the explanation into several steps:

### Step 1: Understanding Molecular Orbital Theory
Molecular orbital (MO) theory describes the behavior of electrons in molecules. Electrons occupy molecular orbitals that are formed from the combination of atomic orbitals.

### Step 2: Identifying the Electrons in Lithium
Lithium (Li) has an atomic number of 3, which means each lithium atom has 3 electrons. In a \( Li_2 \) molecule, there are a total of 6 electrons (3 from each Li atom).

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