Reference(NCERT book of India);
My professor has taught me that $\ce{Na2O}$ and $\ce{Na2O2}$ are the most common oxides of sodium, but in my reference book it is written that they are $\ce{NaO2}$ and $\ce{Na2O2}$. I have searched the net but couldn't find anything about their relative occurrence (percentage). Can anyone please clarify which of the above is correct?