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What term is used for atoms that have the same number of protons but different numbers of neutrons?

  1. Elements

  2. Isotopes

  3. Compounds

  4. Molecules

The correct answer is: Isotopes

The correct term for atoms that have the same number of protons but different numbers of neutrons is indeed "isotopes." Isotopes are variants of a particular chemical element that share the same atomic number (indicating the number of protons) but differ in their mass number because of the variation in neutron count. This difference in neutrons leads to distinct physical properties, although the chemical properties of isotopes of the same element remain largely unchanged. Understanding this concept is crucial in fields such as chemistry and nuclear physics, as isotopes can exhibit different stability and reactivity. For example, carbon-12 and carbon-14 are both isotopes of carbon, with carbon-14 being radioactive and useful in radiocarbon dating. In contrast to isotopes, "elements" refers to pure substances that consist of only one type of atom identified by its atomic number, "compounds" are formed from two or more different types of elements chemically bonded together, and "molecules" consist of two or more atoms bonded together, which may be of the same or different elements.