 |
|
| A B C D E F G H I J K L M N O P Q R S T U V W X Y Z |
|
|
atomic number
The number of protons in one atom of an element. Naturally occurring elements have atomic numbers ranging from 1 (hydrogen) to 92 (uranium). Atomic number (at. no.) has the symbol Z and is also known as the proton number. It is signified by a subscript number before the symbol for the element; for example, the atomic number for carbon is written 6C. Isotopes of an element all have the same atomic number but a different mass number.
The atomic number gives the following information:
- What the element is: only atoms of the same element have the same atomic number.
- The element's numbered position in the periodic table; the periodic table is arranged in atomic number order.
- The number of electrons in the neutral atom.
Related categories
• ATOMIC AND NUCLEAR PHYSICS
• PHYSICAL CHEMISTRY
• PARTICLE PHYSICS
Also on this site:
Encyclopedia of Alternative Energy & Sustainable Living
Encyclopedia of History
Transport Concepts & Designs (partner site)