Which of the following isotopes is not possible?

• A. Hydrogen-1 (protium): 1 proton, 0 neutrons
• B. Oxygen-10: 8 protons, 2 neutrons
• C. Helium-3: 2 protons, 1 neutron
• D. Carbon-14: 6 protons, 8 neutrons

Answer: (B)

Verified step by step guidance

1. Step 1: Understand that an isotope is defined by the number of protons (which determines the element) and the number of neutrons (which can vary). The total number of protons and neutrons gives the mass number of the isotope.
2. Step 2: Identify the element by its number of protons. For example, oxygen always has 8 protons, carbon has 6 protons, helium has 2 protons, and hydrogen has 1 proton.
3. Step 3: Check the neutron number for each isotope and calculate the mass number by adding protons and neutrons: \(\text{Mass number} = \text{protons} + \text{neutrons}\).
4. Step 4: Evaluate the stability and existence of the isotope by comparing the neutron-to-proton ratio and known isotopes. Extremely low or high neutron numbers for a given element often indicate an impossible or highly unstable isotope.
5. Step 5: Specifically for Oxygen-10 (8 protons, 2 neutrons), note that this isotope has a very low neutron number compared to protons, making it highly unlikely or impossible because oxygen isotopes typically have more neutrons to be stable or even to exist transiently.