Define isotopes and explain how they differ from atoms. In what scenarios would isotopes be particularly relevant?

Isotopes are variants of a chemical element that have the same number of protons but different numbers of neutrons, resulting in different mass numbers. The key difference is that while atoms of an element have a fixed number of protons and neutrons, isotopes can vary in neutron count. Isotopes are particularly relevant in nuclear chemistry, radiometric dating, and medical applications such as imaging.

This answer effectively defines isotopes and distinguishes them from atoms, emphasizing the importance of neutron variation. It also contextualizes their relevance in practical scenarios, demonstrating a comprehensive understanding of the topic.