Question

a neutral atom has the following electron configuration:
1s²2s²2p⁶3s²3p⁶4s²
what is the chemical symbol for the atom?

Explanation:

Step1: Calculate the total number of electrons

For a neutral atom, the number of electrons = number of protons = atomic number.
Calculate the sum of electrons in each orbital:

• \(1s^{2}\): \(2\) electrons
• \(2s^{2}\): \(2\) electrons
• \(2p^{6}\): \(6\) electrons
• \(3s^{2}\): \(2\) electrons
• \(3p^{6}\): \(6\) electrons
• \(4s^{2}\): \(2\) electrons

Sum \(=2 + 2+6 + 2+6 + 2=20\)

Step2: Identify the element based on atomic number

The element with atomic number \(20\) is calcium.

Answer:

\(\text{Ca}\)