Which of the following equations can be used to determine the change in enthalpy of a system?
δhreaction=δhproducts×δhreactants δhreaction=δhproducts÷δhreactants δhreaction=δhproducts+δhreactants δhreaction=δhproducts−δhreactants

Calcium carbonate decomposes at high temperatures to give calcium oxide and carbon dioxide as shown below. caco3(s) cao(s) + co2(g) the kp for this reaction is 1.16 at 800°c. a 5.00 l vessel containing 10.0 g of caco3(s) was evacuated to remove the air, sealed, and then heated to 800°c. ignoring the volume occupied by the solid, what will be the mass of the solid in the vessel once equilibrium is reached?