Describe which particles and how many of each you need to make a neutral beryllium atom. (Round the atomic mass from the periodic table to the nearest whole number to get part of your answer.)
Answer: From the periodic table, beryllium has an atomic number of 4 and a mass of almost 9 amu. Therefore, a neutral beryllium atom has 4 protons, 4 electrons, and 5 neutrons (# neutrons = mass # - # protons).
