Question

question 5 (1 point) which of the following is/are true about isotopes? note: there may be more than one true statement, and all correct answers must be selected to receive full credit the atomic number must be the same the number of protons must be different the mass number must be the same the number of neutrons must be different

Explanation:

1. Recall the definition of isotopes: Isotopes are atoms of the same element with the same atomic number (which equals the number of protons) but different mass numbers (since mass number = protons + neutrons, different neutrons lead to different mass numbers).

• "The atomic number must be the same": Atomic number is the number of protons. For isotopes (same element), atomic number (protons) is same. So this is true.
• "The number of protons must be different": Protons determine the element. Isotopes are same element, so protons (atomic number) are same. This is false.
• "The mass number must be the same": Mass number = protons + neutrons. Since neutrons differ in isotopes, mass number differs. This is false.
• "The number of neutrons must be different": Isotopes have same protons, different mass numbers, so neutrons (mass number - protons) must differ. This is true.

Answer:

• The atomic number must be the same
• The number of neutrons must be different