Chemistry - Oxidation numbers
A key stage in the production of sulfuric acid is the conversion of SO2 to
SO3 according to the equation:
This a redox reaction but is not readily identified as such by the
definitions of oxidation and reduction already encountered. To overcome
this difficulty, numbers called oxidation numbers can be used.
Oxidation numbers, also called oxidation states, are assigned to atoms
according to some relatively simple rules.
The rules for assigning oxidation numbers are used when trying to
determine unknown oxidation numbers. Some simple steps are:
* Write down the formula of the substance
* Assign, using the recognised oxidation number rules, the 'known'
oxidation numbers and a pronumeral e.g. x for the unknown oxidation number
* Proceed with the mathematics
Set up and solve this simple equation.
2 x (+1) + _x_ + 4 x (-2) = 0 - _x_ - 6 = 0 - x = +6
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