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), which has an atomic number of 19, we can follow these steps:

### Step 1: Understand Core Electrons
Core electrons are those electrons that are not involved in bonding and are located in the inner shells of an atom. In contrast, valence electrons are the electrons in the outermost shell that can participate in chemical bonding.

### Step 2: Write the Electronic Configuration
The electronic configuration of potassium (K) is given as:
\[ 1s^2 \, 2s^2 \, 2p^6 \, 3s^2 \, 3p^6 \, 4s^1 \]
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