How many core electrons are presentin `._(19)K` ?
Hint `: 1s^(2) 2s^(2) 2p^(6) 3s^(2) 3p^(6) 4s^(1)`

Explanation

To determine the number of core electrons in potassium (K) with an atomic number of 19, we can follow these steps:

### Step 1: Understand Core Electrons
Core electrons are defined as the electrons that are not involved in bonding. They are located in the inner shells of an atom, while valence electrons are found in the outermost shell.

### Step 2: Write the Electronic Configuration
For potassium (K), which has an atomic number of 19, the electronic configuration can be written as:
- 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹
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