Which of the following pairs represent isotopes?

• A. 16O and 16N
• B. 6C and 14C
• C. 1H and 2He
• D. 23Na and 24Mg

Answer: (B)

Verified step by step guidance

1. Recall the definition of isotopes: isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons.
2. Identify the atomic number (number of protons) for each element in the pairs given. For example, oxygen (O) has 8 protons, nitrogen (N) has 7 protons, carbon (C) has 6 protons, hydrogen (H) has 1 proton, helium (He) has 2 protons, sodium (Na) has 11 protons, and magnesium (Mg) has 12 protons.
3. Compare the atomic numbers in each pair to see if they are the same. If the atomic numbers differ, the pair cannot be isotopes because they are different elements.
4. For pairs with the same atomic number, check if their mass numbers (sum of protons and neutrons) are different. This difference in mass number confirms they are isotopes.
5. Conclude which pair represents isotopes based on having the same atomic number but different mass numbers.