Atoms that have the same atomic number but different atomic masses are called isotopes. The difference in mass arises due to the atoms containing a different number of neutrons for the same number of protons. More »

The modern periodic table is arranged in ascending order according to atomic number. An element's atomic number is equal to the number of protons in each atom. Within this order, elements are arranged into distinct group... More »

The difference between atoms, ions and isotopes is the number of subatomic particles. An atom is the basic building block of matter, the smallest molecule of an element that exists and that cannot be chemically divided b... More »

Atoms of the same element that have different masses are called isotopes. Different masses result when there are different numbers of neutrons. All atoms of a particular element have the same number of protons. More »

According to the National Science Foundation, isotopes are important both to help scientists understand the makeup of atoms in a theoretical sense as well as due to the unique characteristics isotopes of certain elements... More »

All isotopes of the same element share a common number of protons and electrons, though they vary in their relative numbers of neutrons. All isotopes of a given element are chemically identical, and they form bonds with ... More »

The isotopes of an element differ from each other in their mass numbers and the number of neutrons they contain. All of the isotopes of an element, however, contain the same number of protons, which is equal to that elem... More »