How to Use Noble Gas Configuration
- 1). Find the element you are studying on the periodic table. If it is copper, for example, you'll find it in the 4th row or "period".
- 2). Determine which noble gas occurs at the end of the period immediately preceding the period in which your element is found. If you are working with copper, for example, copper is in period 4, so you would want the noble gas at the end of period 3, which turns out to be argon.
- 3). Take the symbol from the periodic table for that noble gas and write it in brackets. The symbol for argon, for instance, is Ar, so you would write it in brackets as [Ar].
- 4). Count how many columns your element is over from the left side of the table. Copper, for example, is 11 columns over. This number will be the number of valence electrons in your element.
- 5). Open the link under the Resources section at the bottom of the page and follow the instructions to write out the remainder of the electron configuration.
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