Question

Which fact was most likely discovered between the time of Mendeleev’s table and the time of Moseley’s table that helped Moseley develop his version?

Answer 1

it is

Step-by-step explanation:

The correct option is THE NUMBER OF PROTONS IN AN ATOM IS DIFFERENT FROM THE ATOM'S TOTAL MASS.

During the time Mendeleev developed his periodic table, scientists believed that the number of protons in an atom determine the mass of that atom. But withing the forty years that separated Mendeleev periodic table from Moseley periodic table it was found out that this was not so, this fact helped Moseley in his own work.

Answer 2

The number of protons in an atom is different than the atom's total mass.

Step-by-step explanation:

Mendeleev had presented the first structured periodic table in 1869. But, in 1913, Henry Moseley developed the modern periodic table. The crucial difference between the two periodic tables is that Mendeleev's periodic table is generated on the basis of the atomic masses of chemical elements while the chemical element's atomic numbers were the main focus of Moseley's periodic table. There were just 56 chemical elements in Mendeleev's periodic table. On the other hand, 74 chemical elements are presented in Moseley's periodic table.