Conventional neutron numbers are based on the approximations that the mass of the electron is zero and that those of the proton and neutron are each equal to unity. It was shown, by using the exact ...

Discover the history, structure, and importance of the periodic table of elements, from Mendeleev’s discovery to modern scientific applications. When you purchase through links on our site, we may ...

One hundred fifty years after Russian chemist Dmitri Mendeleev published his system for neatly arranging the elements, the periodic table it gave birth to hangs in every chemistry classroom in the ...