n. at-om- A part or particle considered to be an irreducible constituent of a specified system.
- The irreducible, indestructible material unit postulated by ancient atomism.
- An extremely small part, quantity, or amount.
- Physics & Chemistry.
- A unit of matter, the smallest unit of an element, having all the characteristics of that element and consisting of a dense,
central, positively charged nucleus surrounded by a system of electrons. The entire structure has an approximate diameter of 10-8 centimeter and characteristically
remains undivided in chemical reactions except for limited removal, transfer, or exchange of certain electrons.
- This unit regarded as a source of nuclear energy. .
-Merriam-Webster's Collegiate Dictionary, tenth edition, 1998
Atoms and Isotopes
Bonds
Dimensional Analysis
