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Isotopes quiz

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  • What defines an isotope of an element?
    Isotopes are atoms of the same element that differ in the number of neutrons.
  • Do isotopes of an element have the same number of protons?
    Yes, all isotopes of an element have the same number of protons.
  • What is the mass number of an atom?
    The mass number is the sum of protons and neutrons in the nucleus of an atom.
  • How do isotopes of an element differ from each other?
    Isotopes differ in the number of neutrons, which leads to different mass numbers.
  • What are the three isotopes of carbon and their neutron counts?
    Carbon-12 has 6 neutrons, Carbon-13 has 7 neutrons, and Carbon-14 has 8 neutrons.
  • Which carbon isotope is the most abundant?
    Carbon-12 is the most abundant, making up about 99% of all carbon atoms.
  • How is the atomic mass of an element determined?
    Atomic mass is the average mass of all the isotopes of an element, weighted by their abundance.
  • What is a radioactive isotope?
    A radioactive isotope is an unstable isotope that decays over time, emitting energy and particles.
  • What is meant by the half-life of a radioactive isotope?
    Half-life is the time required for half of a radioactive sample to decay.
  • How many protons and neutrons does Carbon-14 have?
    Carbon-14 has 6 protons and 8 neutrons.
  • Why do isotopes have different mass numbers?
    Because they have different numbers of neutrons, which changes the total mass number.
  • What happens when the number of protons in an atom changes?
    Changing the number of protons changes the element itself.
  • Name two uses of radioactive isotopes.
    Radioactive isotopes are used in medicine and for radiometric dating of fossils.
  • Why is the atomic mass of carbon (12.011) not a whole number?
    Because it is the weighted average of all carbon isotopes, not just the most common one.
  • What does the emission of energy and particles from a radioactive isotope indicate?
    It indicates that the isotope is decaying and is unstable.