Page 212 - Chemistry eBook
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   Writing a Chemical Formula that Contains Elements With Multiple Oxidation States
   • Some elements have multiple (more than one) oxidation states.
Ns oxidation states are: -3, -2, -1, +1, +2, +3, +4, +5.
Š The element behaves differently in each oxidation state. Therefore, it’s important to express which oxidation state we are using.
Make sure you know your Roman numerals!
Flip to the next card to try out an example.
   • So, here’s the great news. The Regents will give you the oxidation state, expressed as a Roman numeral in parentheses, for an element with multiple oxidation states.
   Nitrogen (IV) oxide.
Š Great! This saves you the work of checking up the oxidation state of the first element. (But you will have to look up the oxidation state of the second element.)
• This is called the STOCK SYSTEM: System of naming a compound with multiple oxidation states using Roman numerals.
  Roman numerals
211 © UNIT 6: MATH IN CHEMISTRY
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