Answer:
C 30 degrees after 25 minutes
Explanation:
A reaction is exothermic if heat is evolved as the reaction proceeds. How do we know if heat was given out in the course of the reaction? We have to measure the temperature of the system using a thermometer as the reaction progresses.
If the temperature becomes higher than room temperature (25 degrees), we can now conclude that the reaction is exothermic and heat was indeed given out during the course of the reaction.
The interaction between the two atoms of H in H2 with the lower energy corresponds to a covalent bond between hydrogen's.
When the two atoms of H form a bond, they are overlapping the individual orbitals to form a new one. Every hydrogen has 1 electron which sits in a 1s orbital and then form one molecular orbital. The energy of H2 is lower than individual hydrogens because the electrostatic interaction between them.
I am sorry i wish i could help you but i dont know the answer either.
