What will happen if heat is provided to pure oxygen?

oxygen does not burn(if that is what you are expecting). combustion is the chemical reaction of a fuel, hydrocarbons, and oxygen. if oxygen has nothing to react with then there can be bo combustion. H20 and CO2 are the result of perfect hydrocarbon combustion. 1 molecule of HC plus 2 molecules of O2 produce H2O and CO2.

Pure oxygen does not burn. Oxygen is asupporterof combustion, not a combustible material(fuel) itself. Combustion reactions are as follows: combustible stuff+O2⟶various oxides+heat

Since combustion is a reaction with oxygen, what's left for oxygen to oxidise? Itself? Not likely. You need a fuel to release heat for a combustion reaction. It might convert to a different form likeplasma (about which you will study later, this comes after gas phase).