1s², 2s², 2p⁶, 3s², 3p⁵
Further explanation
Given
Phosphorus element
Required
The electron configuration
Solution
The energy level is expressed in the form of electron configurations.
Writing electron configurations starts from the lowest to the highest sub-shell energy level. There are 4 sub-shells in the shell of an atom, namely s, p, d and f.
Charging electrons in the sub shell uses the following sequence:
1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d¹⁰, 4p⁶, 5s², 4d¹⁰, 5p⁶, 6s², etc.
Electron configurations are based on the number of electrons in the atomic number.
The atomic number of the phosphorus is 15, so the number of electrons is 15.
The configuration:
1s², 2s², 2p⁶, 3s², 3p⁵