Question

a neutral atom has the following electron configuration:
he2s²2p³
what is the chemical symbol for the atom?
how many electrons does the atom have?
how many 2p electrons are in the atom?

Explanation:

First Sub - Question: Chemical Symbol of the Atom

Step 1: Determine electrons from [He]

The electron configuration of He is $1s^{2}$, so it has 2 electrons.

Step 2: Calculate electrons from $2s^{2}2p^{3}$

For $2s^{2}$, the number of electrons is 2. For $2p^{3}$, the number of electrons is 3.

Step 3: Total number of electrons

Total electrons = electrons from [He] + electrons from $2s^{2}2p^{3}$ = $2 + 2+ 3=7$.

Step 4: Identify the element

An atom with 7 electrons (and thus 7 protons, since it's neutral) is nitrogen, with the chemical symbol N.

Second Sub - Question: Number of Electrons in the Atom

Step 1: Analyze the electron configuration

The electron configuration is $[He]2s^{2}2p^{3}$.

Step 2: Calculate total electrons

He has 2 electrons. $2s^{2}$ has 2 electrons and $2p^{3}$ has 3 electrons. So total electrons = $2 + 2+ 3 = 7$.

Third Sub - Question: Number of $2p$ Electrons in the Atom

Step 1: Look at the electron configuration

The electron configuration is $[He]2s^{2}2p^{3}$.

Step 2: Identify $2p$ electrons

From the configuration $2p^{3}$, the number of $2p$ electrons is 3.

Answer:

• Chemical symbol: N
• Number of electrons: 7
• Number of $2p$ electrons: 3