Question

which neutral atom is isoelectronic with n⁻³? ____________ how many valence electrons does neutral n have? ____________

Explanation:

First Sub - Question: Which neutral atom is isoelectronic with \(N^{3 -}\)?

Step 1: Determine the number of electrons in \(N^{3-}\)

A neutral nitrogen (\(N\)) atom has an atomic number of 7, so it has 7 electrons. The \(N^{3-}\) ion is formed by gaining 3 electrons. So the number of electrons in \(N^{3-}\) is \(7 + 3=10\).

Step 2: Find the neutral atom with 10 electrons

A neutral atom has the same number of electrons as its atomic number. An atom with atomic number 10 is neon (\(Ne\)). So the neutral atom isoelectronic with \(N^{3-}\) is neon.

Second Sub - Question: How many valence electrons does neutral \(N\) have?

Step 1: Recall the electron configuration of nitrogen

The atomic number of nitrogen is 7. The electron configuration of nitrogen is \(1s^{2}2s^{2}2p^{3}\).

Step 2: Determine the valence electrons

Valence electrons are the electrons in the outermost shell. For nitrogen, the outermost shell is the \(n = 2\) shell, which contains \(2s^{2}2p^{3}\) electrons. So the number of valence electrons is \(2 + 3=5\).

Answer:

The neutral atom isoelectronic with \(N^{3-}\) is Ne (neon).
Neutral \(N\) has 5 valence electrons.