Chemistry Ions Section 6 Definitions Valence Electrons
Lewis (Electron) Dot Structures Octet Rule Cation Anion Halide Ion How High Are You? Elements in a group behavesimilarly because ofVALENCE ELECTRONS Electrons in the highestoccupied energy level of anelements atoms For representatives, theGROUP # indicates the # ofv. e. Example:Group 2A has twov.e.s, all in the s sublevel Group 4A?7A? For group A elements, LEWIS DOT STRUCTURES showv.e.s as dots Write the symbol of the element Count the number of valence electrons
When drawing Lewis Dot Structures Write the symbol of the element Count the number of valence electrons Put a dot for each valence electron the element hasaround the symbol in the north, south, east, andwest position There must be one dot in each position before youcan start pairing them For now, there can only be a maximum of 2 at eachposition for a max of 8 total Draw the Lewis Dot Structures for the following elements
Sodium Magnesium Aluminum Sulfur Argon Bromine Great Eight Total # of e- that can be in s and p sublevels?
8 OCTET RULE:When forming compounds, atoms tend toachieve noble gas e- configuration General noble gas e- configuration is ns2np6 Other elements cant be the noble gases, but can be likethem Have a pseudo noble gas configuration (p.n.g.c) Elements will lose or gain electrons to achieve p.n.g.c Elements will take shortest path to NEAREST noble gas Meow Cations form when metals lose one or more electrons toattain pseudo noble gas configuration Losing electrons, or negative particles, makes the element morepositive The name of the cation that forms is simply the elementsname followed by ion Ex.Na loses one electron Na+ or the sodium ion (thats thename) Ex. Ca loses two electrons Ca2+ or the calcium ion Most metals in the representative element group are easy to predict
Transition metals not aspredictable Iron (Fe) can lose two orthree electrons, formingFe2+ or Fe3+ There are exceptions tothe octet rule but theywont be covered Gimme Gimme Nonmetals tend to gain electrons to attain pseudo noble gasconfiguration Gainingelectrons makes the element more negative Name of anion typically ends in ide Example:Chlorine gains one electron Cl- or the chloride ion Br -is bromide ion, O2- is oxide ion Anions from group 7A are called HALIDE IONS Oxidation/Reduction Elements found naturally have already given or takenelectrons to become noble-like Elements can be extracted and saturated with electronsto make them neutral again Ca = 20 p+ and 20 e- will be neutral These pure elements will then try to become like thenobles again An element that has lost an electron has become oxidized An element that has GAINED an electron has becomereduced Section 6 Assignment PG 193 Questions 3-7, 9-10
Also, tell me how many electrons they lose/gain, the symboland name for the ion the following elements will form Magnesium Aluminum Phosphorus Sulfur Rubidium Nitrogen Lithium Fluorine Potassium