Answer:
The atomic <u>theory</u> helps to explain observations such as why ice melts at a particular temperature.
Explanation:
A theory is an idea or a system of ideas intended to explain something. For example, Darwin's theory of evolution explains how different species have come to exist.
The atomic theory is the theory according to which all matter is composed of particles called atoms. Thanks to this knowledge, we know why matter acts the way it does, e.g. why ice melts at a particular temperature.
The “mood” in a poem is the emotional response of the reader to a work.
