The correct answer is exothermic. An exothermic reaction is a reaction that releases heat, and therefore it transfers heat to the surroundings (in this case, the tube), making it warmer. Instead, in an endothermic reaction, the heat is absorbed by the reaction.
No, he should place the He atom and energy on the right, and the H atoms and the heat and energy on the left.
Answer:
D a thermometer
Explanation: It measures and track Celcius and Feirinheit.
