Question

b. write the full ground state electron configuration for these ions.

1. ca⁺²:
2. n³⁻:

Explanation:

Step1: Determine the atomic number of Ca

Calcium (Ca) has an atomic number of 20.

Step2: Consider the charge of $Ca^{2 +}$

A $Ca^{2+}$ ion has lost 2 electrons. So the number of electrons is $20 - 2=18$.

Step3: Write the electron - configuration

Using the Aufbau principle, the electron - configuration of $Ca^{2+}$ is $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}$.

Step4: Determine the atomic number of N

Nitrogen (N) has an atomic number of 7.

Step5: Consider the charge of $N^{3 -}$

An $N^{3 -}$ ion has gained 3 electrons. So the number of electrons is $7+3 = 10$.

Step6: Write the electron - configuration

Using the Aufbau principle, the electron - configuration of $N^{3 -}$ is $1s^{2}2s^{2}2p^{6}$.

Answer:

$Ca^{2+}$: $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}$
$N^{3 -}$: $1s^{2}2s^{2}2p^{6}$