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Phy.Sci.Chap. 17-18
Term | Definition |
---|---|
Element: | any pure substance that is made only of one kind of atom. |
Alchemy: | included aspects of chemistry, philosophy, religion, metallurgy, medicine, and art. |
Monatomic elements: | have one atom in natural state. |
Diatomic elements: | have two atoms in natural state. |
Periodicity: | the repetition of certain properties at regular intervals when elements were placed in order of atomic mass. |
Metals: | belong to families with relatively few valence electrons. These valence electrons are not held very strongly and are easily removed. Luster, malleable, conduct electricity, and ductile. |
Non-metals: | hold their electrons tightly, so their properties are very different from metals. Matte, brittle, do not conduct electricity, not ductile. |
Octet rule: | atoms generally are most stable when they have a full eight electrons in their valence energy level. |
Electron affinity: | deals with the strength of attraction of electrons to un-bonded atoms. |
Electronegativity: | deals with an atom's ability to attract and hold electrons when bonded to other atoms. |
Covalent bonds: | non-metal/non-metal; sharing electrons! |
Ionic bonds: | metal/non-metal; giving away and taking electrons. "Bond, Ionic Bond. Taken, not shared." |
Metallic bonds: | metal/metal; everyone shares the electrons; delocalized. |
Electron Sea Theory: | atoms with weak electronegativities usually have only a few loosely held valence electrons. These atoms bond by sharing their easily lost electrons among many atoms. These mobile electrons are not associated with any specific nucleus. |
Fluorine: | Most electronegative; smallest. |
Francium: | Least electronegative; largest. |