Atom is a basic unit of matter that consists of a dense central nucleus surrounded by a cloud of negatively charged electrons. It is the smallest particle which retains individual properties of the element.
The atomic nucleus contains a mix of positively charged protons and electrically neutral neutrons (except in the case of hydrogen-1, which is the only stable nuclide with no neutrons). The electrons of an atom are bound to the nucleus by the electromagnetic force. Likewise, a group of atoms can remain bound to each other by chemical bonds based on the same force, forming a molecule. An atom containing an equal number of protons and electrons is electrically neutral, otherwise it is positively or negatively charged and is known as an ion. positive ions are called cations and negative ions are called anions
An atom is classified according to the number of protons and neutrons in its nucleus: the number of protons determines the chemical element, and the number of neutrons determines the isotope of the element.
Parts of an atom[edit | edit source]
The atom is the smallest particle that retains the propierties of the element, but they are not the smallest particle existent as they themselves are formed of smaller particles. To better undernstand that imagine that a very cheap man was forced to give any quantity of gold. He would give you an atom of gold, because that's the smallest possible quantity of gold you could have, as anything smaller than that is not gold anymore.
Atoms are composed of
Electrons - Electrons are subatomic particles that cause a negative charge in an atom for balance of positive chage and negative charge. Electrons "swirl" around the shell of the atom, which is like a ring.
References[edit | edit source]
- El universo para Ulises by Juan Carlos Ortega. Page 169