Answer: Thomson
Explanation: It verified J. J. Thomson's work on the atomic structure.
C. the number of protons and neutrons an element has in its nucleus
Answer:
endothermic reaction
Explantion:
The definition for endothermic is:
describing a process that involves the absorption of energy from the surroundings by substances undergoing change.
Think of <em>en-</em>dothermic as energy entering and <em>ex-</em>othermic as energy exiting.