When ethanoic acid reacts with sodium carbonate, the container "feels cold." Thus, the reaction is exothermic.
the energy of the reaction is decreased.
the energy of the universe is increased.
the reaction is endothermic.
the energy of both the reaction and the surroundings is decreased.

at the bottom

explanation:

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.

it takes on an electronical energy

it forms an anion that has a larger radius. anions have a negative charge and are larger than the original atom.