Which describes a way that the Plum Pudding model was shown to be incorrect? 1. Neutrons were shown to be located in the nucleus.

2. Electrons were shown to be located outside the nucleus.

3. Protons were shown to be positively charged.

4. Atoms were shown to contain mostly empty space.

answer: atomic mass was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version.

explanation:

originally atomic mass was used to arrange elements on the periodic table from left to right in a row. each column then shows similar properties of elements of a group.

in modern periodic table, the atoms are arranged in increasing atomic number. as atomic number represents the number of protons in an atom which is unique for every atom.