Which of the following can be determined using the half-life of a radioactive isotope?

• A. The mass number of the isotope
• B. The melting point of the isotope
• C. The time required for half of the radioactive nuclei in a sample to decay
• D. The atomic number of the isotope

Answer: (C)

Verified step by step guidance

1. Understand the definition of half-life: It is the time required for half of the radioactive nuclei in a sample to decay.
2. Recognize that the half-life is a measure of the rate of radioactive decay and does not provide information about physical properties like melting point or nuclear properties like mass number or atomic number.
3. Recall that the mass number is the total number of protons and neutrons in the nucleus, and the atomic number is the number of protons; these are intrinsic properties of the isotope and are not determined by half-life.
4. Note that the melting point is a physical property related to the state of matter and bonding, unrelated to radioactive decay or half-life.
5. Conclude that the half-life specifically allows you to determine the time it takes for half of the radioactive nuclei in a sample to decay, which is a measure of the isotope's stability and decay rate.