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.
