From the given info, we know the amount of heat released when 2 moles of Na is reacted. We're asked for the heat per 0.5 moles. So, (368.6 kJ/2mol)0.5000 mol = 92.15...
Oxidation state of oxygen in H2O2.Since hydrogen has an oxidation state of +1Then we'll be having;(1)2+O2=02 + O2 = OThen bringing the constant to the right side have;O2 = -2...