Answer: d) -705.55 kJ
Explanation:
Heat of reaction is the change of enthalpy during a chemical reaction with all substances in their standard states.

Reversing the reaction, changes the sign of 


On multiplying the reaction by
, enthalpy gets half:


Thus the enthalpy change for the given reaction is -705.55kJ
Answer:
The law of conservation of mass
Explanation:
A chemical equation is an expression of the net composition change associated with a chemical reaction. It shows how a certain amount of reactants yields a certain amount of products. Both of these amounts are measured in moles. Chemical equations often contain information about the state of the reactants: solid, liquid, gas, or aqueous. In addition, they always adhere to the law of conservation of mass, which holds that matter can change form, but cannot be created or destroyed.