What is the Atomic Mass of Oxygen? Improve Improve Like Article Like Save Share Report Atomic Mass of Oxygen is . A) 16 B) 17 C) 15 D) 14 Answer: The atomic mass of Oxygen is 16 amu. Therefore, the correct option is A. Explanation: Atomic Mass of any substance is the sum of the number of protons and the number of neutrons in the nucleus of that atom. For Oxygen, Number of Protons = 8 Number of Neutrons = 8 Thus, Atomic Mass of Oxygen = 8 + 8 = 16 In absolute terms, the average atomic mass of oxygen is 15.99994 amu. It is calculated taking into account all the isotopes of oxygen. Last Updated : 09 Feb, 2024 Like Article Save Article Previous What is a General Formula for an Ester? Next What is the Atomic Mass of Carbon? Share your thoughts in the comments Add Your Comment Please Login to comment...