There are three stable isotopes of oxygen having mass ­numbers 16, 17 and 18. Determine the number of neutrons and protons in each of these.

• A. ¹⁶O: Neutrons = 16, Protons = 8, ¹⁷O: Neutrons = 17, Protons = 8, ¹⁸O: Neutrons = 18, Protons = 8
• B. ¹⁶O: Neutrons = 8, Protons = 8, ¹⁷O: Neutrons = 9, Protons = 8, ¹⁸O: Neutrons = 10, Protons = 8
• C. ¹⁶O: Neutrons = 8, Protons = 8, ¹⁷O: Neutrons = 8, Protons = 9, ¹⁸O: Neutrons = 8, Protons = 10
• D. ¹⁶O: Neutrons = 8, Protons = 16, ¹⁷O: Neutrons = 8, Protons = 17, ¹⁸O: Neutrons = 8, Protons = 18

Answer: (B)