How many protons does radium have?
Radium has 88 protons.
Radium has 88 protons, and therefore 88 neutrons. Together 176 particles is too many to fit into a diagram easily. I've done a seach on the Internet and can not find a diagram for the inner structure of Radium but have found a good electron diagram, if that is any help? It is here: [http://upload.wikimedia.org/wikipedia/commons/thumb/1/13/Electron_shell_088_Radium.svg/558px-Electron_shell_088_Radium.svg.png Radium (WikiCommons)]
The neutrons aren't really relevant, since we don't know what the mass of the radium nucleus was and the element is determined strictly by the number of protons anyway. Radium has an atomic number of 88; losing 4 protons would make the atomic number 84, which is polonium. (This is probably really a two-step process: radium -> radon -> polonium, where each step is an alpha decay.)
When 226radium undergoes alpha decay it becomes 222radon. Note that an alpha particle is composed of two protons and two neutrons. Note also that that the alpha particle is also a helium-4 nucleus. There are 4 nucleons (protons or neutrons) in the alpha particle (or helium-4 nucleus). If we look at 226radium and subtract 4 from the 226, we get 222. The 4 comes from the total number of protons and neutrons in the alpha…