The subatomic particles that identifies an element and also represents its atomic number would be A. The number of protons.
Your reaction
.. Fe + O2 ---> FexOy
for this reaction..
.. the Fe on the left is in the 0 oxidation state
.. the Fe on the right is in the +(2y/x) oxidation state
.. the O on the left is in the 0 oxidation state
.. the O on the right is in the -2 oxidation state
meaning
.. the O is reduced... . . (it's reduced in oxidation state)
.. the Fe is oxidized.. . .(oxidation state increased)
this is a REDOX reaction
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AND.. it's also a synthesis reaction.. (aka combination reaction)
Ice because the molecules have less movement in solids
I don't know sorry I really need point