Answer : The value of
for this reaction is 36.18 kJ
Explanation :
First law of thermodynamic : It states that the energy can not be created or destroyed, it can only change or transfer from one state to another state.
As per first law of thermodynamic,

where,
= internal energy of the system
q = heat added or rejected by the system
w = work done
As we are given that:
q = 38.65 kJ
w = -2.47 kJ (system work done on surrounding)
Now put all the given values in the above expression, we get:


Therefore, the value of
for this reaction is 36.18 kJ
Answer: This is hard to do accurately, but here is my best assessment.
Explanation:
Experiment: B - describes how the experiment was done
Conclusion: A - The data support the prevailing hypothesis
Research: D - This is what we analyzed
Analysis: C - We compared the data
Its b because it explains it better than a waterfall does