What is the usual symbol for (a) an electron (b) a proton, and (c) a neutron?
(a) Electron : e-
(b) Proton : p+
(c) Neutron : n
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)___ .