Atoms and the subatomic particles that comprise them, are the elementary building blocks of material substances. Although the term atom, derived from the Greek word atomos, meaning indivisible, would seem inappropriate for an entity that, as science...

Atoms are the elementary building blocks of material substances. Although the term atom, derived from the Greek word atomos, meaning indivisible, would seem inappropriate for an entity that, as science has established, is divisible, the word atom still...

Atomic theory, first put in a quantitative conceptual framework by John Dalton, and quantum theory, which emerged in the 1920s as a result of the work of Werner Heisenberg, Erwin Schrödinger, and Max Planck, are the cornerstones of our present-day...

All matter, for practical purposes, is composed of atoms. They are discrete entities and indivisible under normal circumstances. This has a profound effect on all of chemistry in that any compound must be composed of a whole number of atoms. That is,...

In chemistry and physics, an atom (Greek ἄτομος or átomos meaning "the smallest indivisible particle of matter, i.e. something that cannot be divided") is the smallest particle still characterizing a chemical element. An atom consists of a dense...

A.Q. Khan, the scientist who became a national hero for developing Pakistan's atomic bomb and went on to sell nuclear secrets abroad, can leave house arrest to meet with friends and relatives, officials said Monday.In his first public statement in years, Khan told The Associated...

Israel is looking to a U.S.-India nuclear deal to expand its own ties to suppliers, quietly lobbying for an exemption to non-proliferation rules so it can legally import atomic material, according to documents made available Tuesday to The Associated Press.The move is sure to raise...

Revolutionary ideas require great concentration to form and particular care to spread.Those skills helped physics pioneer Niels Bohr redefine how we look at the world.His Nobel Prize-winning theories helped people understand quantum mechanics and atomic structure. Those concepts leapt from his unbreakable concentration. When pondering...

Intelligence officials reported increased activity Tuesday around North Korea's main nuclear reactor, indicating the country may be preparing to uphold its agreement to shut down the plant.North Korea missed last Saturday's deadline for shuttering the reactor because of a dispute over $25 million in North...

Contains notes about atoms stating definitions and equations.