10.0g of sodium reacts with an excess of water with ΔH = –79.91 kJ, whereas 20.0g of sodium oxide react with an excess of water with ΔH = –76.76 kJ.
Standard enthalpy of formation of water: ΔHf = −286 kJ mol
Calculate the standard enthalpy change of formation of sodium oxide.
I'm not entirely sure how to set this problem up, could someone please help me. Thank you!