Consider the following balanced thermochemical equation for the decomposition of the mineral magnesite:
a. Is heat absorbed or released in the reaction?
b. What is ΔHrxn for the reverse reaction?
c. What is ΔH when 6.50 mol of CO2 reacts with excess MgO?
d. What is ΔH when 40.50 g of CO2 reacts with excess MgO?