I am trying to figure out the number of protons and neutrons in Sodium-24. How would I do that? And how can I figure out what element has 50 protons and 70 neutrons? Thanks for clarifying these questions.
Chemistry Level A - DrBob222, Sunday, April 19, 2009 at 8:27pm
Look at the periodic table. If you know it is Na, the atomic number is 11; therefore, the # protons is 11. The number of nucleons (protons + neutrons) = 24 so the number of neutrons = 24-#protons.
Given that info, the element with 50 protons MUST be element #50. Look at the table and read it off. If it has 50 protons and 70 neutrons, it must have mass number of 70 + 50 = 120. I would think 50120Sn. Check my work.