Which isotope of neon has 10 neutrons?

• A. Neon-20
• B. Neon-21
• C. Neon-20 has 10 protons and 10 neutrons
• D. Neon-22

Answer: (C)

Verified step by step guidance

1. Recall that the number of protons in neon is always 10, since the atomic number of neon is 10.
2. Understand that the isotope notation (e.g., Neon-20) indicates the mass number, which is the sum of protons and neutrons in the nucleus.
3. Use the formula for the number of neutrons: \(\text{Number of neutrons} = \text{Mass number} - \text{Number of protons}\).
4. Calculate the number of neutrons for each isotope by subtracting 10 (protons) from the mass number: for Neon-20, neutrons = \$20 - 10\(; for Neon-21, neutrons = \)21 - 10\(; for Neon-22, neutrons = \)22 - 10$.
5. Identify which isotope has 10 neutrons by matching the calculated neutron number to 10.