Presentation on theme: "Chem-To-Go Lesson 13 Unit 4 IONIC BONDING - WRITING FORMULAS Need a periodic table!"— Presentation transcript:
Chem-To-Go Lesson 13 Unit 4 IONIC BONDING - WRITING FORMULAS Need a periodic table!
Most neutral atoms are unstable. In order to become stable, most atoms need achieve 8 valence electrons. Metals lose electrons to become stable. Many nonmetals gain electrons to become stable. Many nonmetals share electrons to become stable. Part 1: Ionic Bonding Metals bonding to nonmetals Involves losing electrons & gaining electrons [ions] Part 2: Covalent Bonding Nonmetals bonding to nonmetals Involves sharing valence electrons [no ions] QUICK OVERVIEW
A sodium atom loses an electron to become stable. The atom becomes a +1 ion. A chlorine atom gains the electron to become stable. The atom becomes a -1 ion. Opposites attract. The Na +1 and Cl -1 are bonded by a force of attraction. Notice that the overall charge of the compound is neutral. IONIC BONDING
Metal: Magnesium Nonmetal: Nitrogen MORE COMPLEX EXAMPLE A simple 1 to 1 ratio of atoms doesn’t address the needs of each atom.
EXAMPLE: calcium and phosphorus CRISS-CROSS FORMULA WRITING NOTICE: THE FINAL FORMULA IS NEUTRAL.
EXAMPLE: aluminum and sulfate ion CRISS-CROSS FORMULA WRITING NOTICE: THE FINAL FORMULA IS NEUTRAL.
EXAMPLE: tin(II) and carbonate ion CRISS-CROSS FORMULA WRITING NOTICE: THE FINAL FORMULA IS NEUTRAL.
EXAMPLE: Sodium hypochlorite WRITING FORMULAS FROM NAMES
EXAMPLE: magnesium phosphate WRITING FORMULAS FROM NAMES
All final formulas are neutral. No superscripts or charges appear in the final formula. Always and only reduce subscripts in the final answer, but never change a polyatomic ion. Use parentheses around polyatomic ions when a subscript is needed. SUMMARY