An atom 17 protons, 17 electrons and 18 neutrons has a mass number of

An atom 17 protons, 17 electrons and 18 neutrons has a mass number of

Answer Details

The mass number of an atom is the sum of the number of protons and the number of neutrons in the nucleus of the atom. Therefore, the mass number of the atom with 17 protons and 18 neutrons is: Mass number = number of protons + number of neutrons = 17 + 18 = 35 Hence, the correct option is 35.