
Atom | Definition, Structure, History, Examples, Diagram, & Facts ...
4 days ago · Chemical elements are made up of only one type of atom—gold contains only gold atoms, and neon contains only neon atoms--and they are ranked in order of their atomic …
Atom - Quantum Mechanics, Subatomic Particles, Electrons
4 days ago · In Heisenberg’s method, properties of atoms are described by arrays of numbers called matrices, which are combined with special rules of multiplication. Today physicists use …
Atomic physics | Structure, Particles & Energy | Britannica
It attempts to describe and account for the properties of molecules and atoms and their constituents— electrons, protons, neutrons, and other more esoteric particles such as quarks …
Atom - Mass, Isotopes, Structure | Britannica
Nov 14, 2025 · The easiest way to see this is to imagine building up complex atoms by starting with hydrogen and adding one proton and one electron (along with the appropriate number of …
atom - Students | Britannica Kids | Homework Help
Atoms are made up of three basic types of particle: protons, neutrons, and electrons. These particles (as well as other particles smaller than atoms) are known as subatomic particles.
Atom - Electrons, Nucleus, Bonds | Britannica
6 days ago · Atom - Electrons, Nucleus, Bonds: Once the way atoms are put together is understood, the question of how they interact with each other can be addressed—in particular, …
atom - Kids | Britannica Kids | Homework Help
The tiny particles called atoms are the basic building blocks of all matter. Atoms can be combined with other atoms to form molecules, but they cannot be divided into smaller parts by ordinary …
Atom - Development, Theory, Structure | Britannica
4 days ago · Democritus believed that atoms were uniform, solid, hard, incompressible, and indestructible and that they moved in infinite numbers through empty space until stopped. …
Periodic table | Definition, Elements, Groups, Charges, Trends,
Dec 10, 2025 · Detailed understanding of the periodic system has developed along with the quantum theory of spectra and the electronic structure of atoms, beginning with the work of …
Mole | Definition, Number, & Facts | Britannica
Nov 7, 2025 · The number of atoms or other particles in a mole is the same for all substances. The mole is related to the mass of an element in the following way: one mole of carbon-12 …