Here are the steps in chronological order concerning how to write an abbreviated electron configuration for an element:
1. Determine the atomic number of the element. This is the number of protons in the nucleus of the atom and is usually found on the periodic table.
2. Write the symbol of the previous noble gas in brackets. This represents the electron configuration of the noble gas, which is the closest complete energy level below the element in question.
3. Write the configuration for the remaining electrons after the noble gas. This is done by writing the number of electrons in each subshell, followed by the letter that represents the subshell (s, p, d, or f), and then a superscript to indicate the number of electrons in that subshell.
Check that the total number of electrons in the abbreviated configuration matches the atomic number of the element.
For example, to write the abbreviated electron configuration for oxygen (O), we would follow these steps:
- The atomic number of oxygen is 8.
- The previous noble gas is helium (He), which has an electron configuration of 1s^2. We write this as [He].
- The remaining electrons in oxygen occupy the 2s and 2p subshells. There are 6 electrons in total, with 2 in the 2s subshell and 4 in the 2p subshell. We write this as 2s^2 2p^4.
Checking the total number of electrons, we have 2 + 4 = 6, which matches the atomic number of oxygen.
This way, you can write an abbreviated electron configuration for an element.
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