Different versions of the same element, like pictured below, add known as _ The number 12,13 and 14 refer to the _

Sorry i dont understand the question can you rephase it?

Hello thereone of the following properties was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version. which property fits this description? answer: atomic mass  was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version.