Write the Lewis dot symbols and predict the valencies for the elements:
Phosphorous

Explanation

To determine the Lewis dot symbols and predict the valency for phosphorus, we will follow these steps:

### Step 1: Identify the Atomic Number and Electron Configuration
Phosphorus (P) has an atomic number of 15, which means it has 15 electrons. The electron configuration of phosphorus is:
\[ 1s^2 \, 2s^2 \, 2p^6 \, 3s^2 \, 3p^3 \]

### Step 2: Determine the Valence Electrons
The valence electrons are the electrons in the outermost shell. For phosphorus, the outermost shell is the third shell (n=3), which contains:
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