What are isotopes?

Isotopes are defined as atoms of the same element that possess the same number of protons but have different numbers of neutrons. This means that while isotopes retain the same atomic number (which determines the element's identity), they differ in atomic mass due to the variation in neutron count. For example, carbon has several isotopes, including carbon-12, which has six neutrons, and carbon-14, which has eight neutrons.

The uniqueness of isotopes lies in their nucleus structure, which can lead to differences in stability and radioactive properties, making them important in various scientific fields, including medicine, archaeology, and environmental science. This understanding of isotopes is fundamental, especially in veterinary medicine where isotopes can be used for diagnostic imaging and treatment.

The other options do not accurately represent the concept of isotopes. The first option describes elements, which could refer to different atoms altogether rather than variations of the same element. The third option mistakenly focuses on electron differences rather than neutron variations. The fourth option describes ions, which are not isotopes, as it pertains only to electrons.