An atom is so small that a single drop of water contains more than a billion atoms. Although tiny, atoms are mostly empty ...

It also tells us that chlorine has 18 neutrons (35 - 17) and, as the number of electrons and protons are equal in a neutral atom, chlorine also has 17 electrons. The relative mass of a nucleus is ...

The nucleus is very small compared to the atom as a whole: as electrons are even smaller, most of an atom is empty space the diameter of a nucleus can be 100,000 times less than the diameter of an ...

University of Queensland scientists have cracked a long-standing puzzle in nuclear physics, showing that nuclear polarization ...

When two hydrogen atoms get close enough, the electron from each atom feels an attraction from the proton in the other atom's nucleus. This attraction pulls the atoms together. The electrons end up ...

An atom becomes radioactive when its nucleus contains too many or too few neutrons. Try to keep the same number of neutrons and protons as you build your atom. If the imbalance is too great ...

The electrons surround the nucleus in 3 dimensions but it is easier to show an energy level model in two dimensions like the model that looks like a target. This energy level model shows two electrons ...

These additions made sense in Bohr’s picture of the atom: if the electron is moving along a circular orbit around the atomic nucleus, it would have an angular momentum; and as a charged body in ...

The IAEA's NUCLEUS information resource portal provides access to over 100 scientific, technical and regulatory resources, including databases, applications, publications and training material. As it ...

Having a “magic” number of protons or neutrons means there are enough to fully occupy the nuclear valence shells (outermost orbits around the nucleus) in an atom and give it stability.

The difference, though, lies in the hydrogen atoms. In ordinary water, each hydrogen atom has just a single proton in its nucleus. In heavy water, each hydrogen atom is indeed heavier, with a ...