Determine whether each of the following changes represents oxidation or reduction.

I dont know really your options in this question bt I guess they are 1) Fe2O3 to Fe 2) CH3CH2OH to CH3CH3 3) Mg to MgO 4) NO3- to NO2- 5)Ca to CaO 6) KClO3 to KCl 7) SO2 to S 8) C2H6O to C2H4O2
And if its like that we can say that All the ones that are REDUCTION are: 1,2,4,6 and 7 and the ones that are OXIDATION are 3,5 and 8. For you to remember we can say that oxidation involves loss of electrons and reduction involves gain of electrons 

Yes it would be a physical change.