No one is 100% sure when particles of matter originated however scientist believe it had to be some time before the Big Bang
Answer:
i think its d i may be wrong
Explanation:
The answer for this would be 69.6
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