Chemistry

Given the following reaction use Stoichiometry to answer the following questions: 

4Fe (s) + 3 O2 (g) → 2 Fe2O3 (s) ∆H° = -1.65 x 103 kJ 

How many mol of O2 are required to form 3.20 mol Fe2O3? 
How much heat is exchanged when 14.3 kg of iron (Fe) rusts? 
How much (g) of rust, Fe2O3, is formed when 200. kJ of heat is released? 

Calculate the standard change in enthalpy, ΔH°rxn, for the decomposition of calcium carbonate to calcium oxide: (Sample Problem 6.10) 

CaCO3 (s) → CaO (s) + CO2 (g) 
Given that: 
ΔH°f CaCO3 (s) = -1206.9 kJ/mol 
ΔH° CaO )s) = -635.1 kJ/mol 
ΔH° CO2 (g) = -393.5 kJ/mol