An atoms contains 15 protons, 15 electrons, and 16 neutrons. Which of the following combinations of particles is an isotope of that atom?
An atom of phosphorus has the symbol 3115P. Give the number of protons, neutrons and electrons in an atom of phosphorus. Number of protons __(A)___. Number of neutrons __(B)___ . Number of electrons __(C)___ .