Energy from chemical Reactions. Thanks?

Question

2C2H6 (g) + 7O2 (g) -------> 4CO2 (g) + 6H2O (l); H= -3120kjmol-L

1, Calculate the energy released when 10L at SLC, of ethane gas burns according to the equation

2. What volume of ethane, measured at STP, must be burnt in order to yeild 100kj of heat energy?

Answer 1

The reaction evolves 939 kJ of heat per 2 mol HCN formed. What is the value of q for this reaction, and is the reaction endothermic or exothermic?

+469.5 kJ ; endothermic

+939 kJ ; endothermic

-939 kJ ; exothermic

-469.5 kJ ; exothermic

-1879 kJ ; exothermic