Which of the following isotopes has 8 neutrons in its nucleus?

• A. C-13
• B. O-15
• C. C-14
• D. O-17

Answer: (D)

Verified step by step guidance

1. Recall that the number of neutrons in an isotope is given by the formula: \(\text{Number of neutrons} = \text{Mass number} - \text{Atomic number}\).
2. Identify the atomic number (number of protons) for each element: Carbon (C) has an atomic number of 6, and Oxygen (O) has an atomic number of 8.
3. Calculate the number of neutrons for each isotope by subtracting the atomic number from the mass number: For example, for C-13, neutrons = 13 - 6.
4. Perform this calculation for each isotope: C-13, O-15, and C-14, to find how many neutrons each contains.
5. Compare the calculated neutron numbers to find which isotope has exactly 8 neutrons.