Helium-4

The element that I am presenting is helium. Helium has the atomic symbol of He. The atomic number is 2 and it has an atomic mass of 4. It is in the Noble Gases classification which means it is in group 18 of the periodic table and has an oxidation number of 0. It will float in water because at 293 K, it is 0.1785 grams. It’s PEN (Protons, Electrons, Neutrons) is 2, 2, 2 because the atomic number is 2 so it has 2 protons and 2 electrons, and the atomic mass is 4 and 4-2 is 2. That means that the PEN is 2, 2, 2.



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