All atoms of the same element are alike in that each atom has the same ____________________. anumber of protonsbatomic masscnumber of neutronsdmass number

Answering the Question

All atoms of the same element are alike in that each atom has the same number of protons.

The number of protons in the nucleus of an atom determines its atomic number, which is unique to each element. This means that, regardless of the isotope or the number of neutrons an atom might have, the defining characteristic that makes all atoms of a specific element identical is their proton count. For example, all carbon atoms have six protons, which defines them as carbon.

In summary, the correct option is a. number of protons. It is essential to understand that while atoms of the same element may vary in their number of neutrons (leading to different isotopes) or differing mass numbers (the total number of protons and neutrons), the proton count remains constant for all atoms of that element.