Gryphon is the 16,347 th most popular name of all time. How many people with the first name Gryphon have been born in the United States? From 1880 to 2016, the Social Security Administration has recorded 485 babies born with the first name Gryphon in the United States.
Making the world better, one answer at a time. 25 is the number of protons and neutrons added together. The atomic number of Mg is 12 which is the number of protons. So 25 - 12 = 13 neutrons.
Rating Newest Oldest. Best Answer: It depends on which isotope. But since phosphorus has an atomic number of 15, signifying 15 protons in the nucleus, and an atomic mass of 30.97, signifying 31 total nucleons, the average number of neutrons must be 31 - 15 = 16. Most atoms have a number of neutrons that is close to the number of protons. Phosphorus with an atomic mass of 31 is the only isotope that occurs in nature, but heavier phosphorus nuclei have been synthesized in labs.