Term | Definition |
Atom | An atom with one of the electrons replaced by some other particle. |
Element | A component or constituent of a whole or one of the parts into which a whole may be resolved by analysis |
Nucleus | A central part about which other parts are grouped or gathered |
Electron Shell | A grouping of electrons surrounding the nucleus of an atom; "the chemical properties of an atom are determined by the outermost electron shell" |
Proton | A positively charged elementary particle that is a fundamental constituent of all atomic nuclei. |
Neutron | An elementary particle having no charge, mass slightly greater than that of a proton, and spin of ½: a constituent of the nuclei of all atoms except those of hydrogen. |
Isotape | Any of two or more forms of a chemical element, having the same number of protons in the nucleus, or the same atomic number, but having different numbers of neutrons in the nucleus, or different atomic weights. |
Electron | An elementary particle that is a fundamental constituent of matter, having a negative charge |
Ion | an electrically charged atom or group of atoms formed by the loss or gain of one or more electrons, as a cation |
Representative Element | A tabular arrangement of the elements according to their atomic numbers so that elements with similar chemical properties are in the same column. |
Transition Element | Any element in any of the series of elements with atomic numbers 21–29, 39–47, 57–79, and 89–107, that in a given inner orbital has less than a full quota of electrons. |
Period | Compare group one of the horizontal rows of elements in the periodic table. Each period starts with an alkali metal and ends with a rare gas. |