CP Chemistry: Ionic Compounds
October 06, 2011
Representative Elements
- Group # (roman numeral) tells you how many outer
(valence) electrons each element has
- all elements (except noble gases) want to gain or lose
electrons to achieve a complete outer shell
• IA
- 1 outer electron - form +1 ions by losing one e
• IIA
- 2 outer electrons - form +2 ions by losing two e
• IIIA
- 3 outer electrons - form +3 ions by losing three e-
• IVA
- 4 outer electrons - can form either +4 or -4 ions, usually don't
- 5 outer electrons - form -3 ions by gaining three extra e-
• VA
-
• VIA - 6 outer electrons - form -2 ions by gaining two extra e• VIIA - 7 outer electrons - form -1 ions by gaining one extra e
• VIIIA - 8 outer electrons - noble gases do not ionize or share!
- # of outer (valence) electrons determines how an atom of a
particular element reacts!
- every atom "wants" a complete outer shell of electrons
- like noble gases!
- there are two ways an atom can accomplish this:
- gain electrons until they have 8 in the outer shell
- nonmetals - form negative ions (anions)
- lose electrons until their outer shell is empty
- metals - form positive ions (cations)
http://www.kentschools.net/ccarman/
CP Chemistry: Ionic Compounds
Metals lose electrons:
Nonmetals gain electrons:
http://www.kentschools.net/ccarman/
October 06, 2011
CP Chemistry: Ionic Compounds
Formation of an ionic bond:
http://www.kentschools.net/ccarman/
October 06, 2011