Questions: How many unpaired electrons are there in the following ground-state atoms and ions? If none, enter a zero in the answer box. O has unpaired electrons P3- has unpaired electrons

How many unpaired electrons are there in the following ground-state atoms and ions? If none, enter a zero in the answer box.

O has unpaired electrons

P3- has unpaired electrons

Transcript text: How many unpaired electrons are there in the following ground-state atoms and ions? If none, enter a zero in the answer box. O has $\square$ unpaired electrons $\mathrm{P}^{3-}$ has $\square$ unpaired electrons

Solution

Solution Steps

Step 1: Determine the Electron Configuration of Oxygen (O)

Oxygen (O) has an atomic number of 8.
The electron configuration for oxygen is $1s^2 \, 2s^2 \, 2p^4$.

Step 2: Identify Unpaired Electrons in Oxygen

The $2p$ subshell can hold a maximum of 6 electrons.
In oxygen, the $2p$ subshell has 4 electrons: $2p^4$.
Electrons fill orbitals singly before pairing up (Hund's rule).
Therefore, in the $2p$ subshell, there are 2 unpaired electrons.

Step 3: Determine the Electron Configuration of $\mathrm{P}^{3-}$

Phosphorus (P) has an atomic number of 15.
The electron configuration for neutral phosphorus is $1s^2 \, 2s^2 \, 2p^6 \, 3s^2 \, 3p^3$.
The $\mathrm{P}^{3-}$ ion has gained 3 additional electrons, making the configuration $1s^2 \, 2s^2 \, 2p^6 \, 3s^2 \, 3p^6$.

Step 4: Identify Unpaired Electrons in $\mathrm{P}^{3-}$

The $3p$ subshell in $\mathrm{P}^{3-}$ is fully filled with 6 electrons: $3p^6$.
A fully filled subshell has no unpaired electrons.
Therefore, $\mathrm{P}^{3-}$ has 0 unpaired electrons.