Engage
Earlier in this course you learned about reactions that give off or take in energy. View the video on each tab to see an example of each type of energy based on whether they give off or take in energy.
In an endothermic reaction, energy is taken in, which cools the surrounding environment.
This video shows an example of an endothermic reaction.
In this demonstration, a white, powdery substance is added to a beaker of liquid. The initial temperature is 24.7 °C. As the substances react, the temperature of the mixture decreases to 18.2 °C. This shows energy being absorbed and cooling down the surroundings.
In an exothermic reaction, energy is given off which warms the surrounding environment.
Question
As an experiment, a student put zinc in hydrochloric acid. The student observed that the outside of the test tube got very hot as the reaction occurred. What was happening with energy in this reaction? What type of a reaction was occurring?
Energy was being given off during this reaction. It was an exothermic reaction.
Reflection
Which type of reaction (endothermic or exothermic) happens in the MRE? Explain why you think it is this type?
