Question

consider a reaction where the reactants are at room temperature, and the products feel colder than their surroundings. what can you conclude about the reaction?
a. it is endothermic.
b. it is exothermic.
c. it does not have an activation energy.
d. it has increased entropy.

Explanation:

• An endothermic reaction absorbs heat from the surroundings. When products feel colder than the surroundings, it indicates that heat has been absorbed from the surroundings by the reaction, which is a characteristic of an endothermic reaction.
• All chemical reactions have an activation energy (even spontaneous ones), so option C is incorrect.
• Just because the products are colder doesn't directly tell us about entropy change (option D is not directly deducible from the given information about temperature of products relative to surroundings).
• Since it's endothermic (absorbing heat), it can't be exothermic (option B is wrong).

Answer:

A. It is endothermic.