The elements P (Atomic weight 39) and Q (Atomic weight 80) contain 20 and 45 neutrons respectively their nucleus. Give their electronic arrangements separately.

Explanation

To find the electronic arrangements of elements P and Q, we will follow these steps:

### Step 1: Determine the number of protons for each element.
The number of protons in an element is equal to its atomic number. The atomic number can be calculated using the formula:

\[ \text{Number of protons} = \text{Atomic weight} - \text{Number of neutrons} \]
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