Which phrase best describes the element carbon-14?

• A. A molecule containing 14 carbon atoms
• B. An isotope of carbon with 6 protons and 8 neutrons
• C. A stable isotope of carbon with 7 protons and 7 neutrons
• D. An ion of carbon with 14 electrons

Answer: (B)

Verified step by step guidance

1. Understand that carbon-14 refers to a specific form of the element carbon, characterized by its atomic structure.
2. Recall that the atomic number of carbon is 6, which means every carbon atom has 6 protons.
3. Recognize that the number 14 in carbon-14 represents the mass number, which is the sum of protons and neutrons in the nucleus.
4. Calculate the number of neutrons by subtracting the number of protons from the mass number: \(\text{neutrons} = 14 - 6\).
5. Conclude that carbon-14 is an isotope of carbon with 6 protons and 8 neutrons, distinguishing it from other isotopes by its neutron count.