What is the ground state energy of electron in case of `._3Li^7` ?

Explanation

To find the ground state energy of the electron in the lithium ion \( \text{Li}^{2+} \), we can follow these steps:

### Step 1: Identify the atomic number and the number of electrons
Lithium (\( \text{Li} \)) has an atomic number \( Z = 3 \). In the case of \( \text{Li}^{2+} \), two electrons are removed, leaving us with one electron.

### Step 2: Recognize that \( \text{Li}^{2+} \) behaves like a hydrogen-like atom
Since \( \text{Li}^{2+} \) has only one electron, it behaves like a hydrogen-like atom. The formula for the energy of an electron in a hydrogen-like atom is given by:

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