To find the charge on ions we can either use the Periodic Table or, for polyatomic ions, a table of common ions.

For ions of individual elements, like Sodium, Nitrogen, or Oxygen, we can follow the trend on the Periodic Table. For example, ions in Group 1 have a 1+ charge. Sodium (Na) forms Na+ ions. Nitrogen (N) is N 3- and Oxygen (O) forms O 2- ions.

To figure out the charge on polyatomic ions we can either have them memorized or, if we are allowed by our instructor, look them up on a table of common polyatomic ions. For example, the sulfate ion is SO4 2-. The Nitrate ion is NO3 - .

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Resources:

Periodic Tables used in this video:
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Table of Common Polyatomic Ions:
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Naming and Formula writing for ionic compounds:
[ Ссылка ]

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Determining the charge on ions is a key skill in chemistry. It is used extensively in naming and writing formulas for chemical compounds, in net ionic equations, chemical bonding, etc. A good strategy is to memorize the pattern for ions in the Periodic Table first. Then memorize the most common polyatomic ions. Being able to quickly recall the charges ion ions will save time on exams, homework, and make life easier.

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