Ionic Formulas and Nomenclature

Formulas What types of elements are found in ionic compounds? What types of elements are found in ionic compounds? What holds the elements together? What holds the elements together? Even though there are ions in ionic compounds, the overall compound must be neutral. Even though there are ions in ionic compounds, the overall compound must be neutral.

Electrolytes What type of compounds are electrolytes? What type of compounds are electrolytes? Why are ionic compounds electrolytes? Why are ionic compounds electrolytes? Consider sodium chloride: Consider sodium chloride: Is this an electrolyte? Is this an electrolyte? Why? Why? Consider sucrose (sugar, C 12 H 22 O 11 ): Consider sucrose (sugar, C 12 H 22 O 11 ): Is this an electrolyte? Is this an electrolyte? Why? Why? Consider ammonium chloride (NH 4 Cl): Consider ammonium chloride (NH 4 Cl): Is this an electrolyte? Is this an electrolyte? Why? Why?

Conductivity of Ammonium Chloride Why does it light up? Why does it light up? What type of bonding actually occurs in ammonium chloride? What type of bonding actually occurs in ammonium chloride? Where are the ions in NH 4 Cl? Where are the ions in NH 4 Cl?

Two Types of Ions Monatomic ions – ions made of a single atom. Monatomic ions – ions made of a single atom. Polyatomic ions – ions made of many atoms Polyatomic ions – ions made of many atoms Polyatomic ions can be found on your reference table. Polyatomic ions can be found on your reference table.

Ionic Formulas Activity

Writing Ionic Formulas A compound made from barium and phosphate ions. A compound made from barium and phosphate ions. Figure out the charges on the ions involved. Figure out the charges on the ions involved. Ba 2+ Ba 2+ PO 4 3- PO 4 3- Find the lowest common multiple of the charges: Find the lowest common multiple of the charges: LCM of 2 and 3 is 6 LCM of 2 and 3 is 6 When you have 6 total positive charges and 6 total negative charges the compound will be neutral. When you have 6 total positive charges and 6 total negative charges the compound will be neutral. Determine the individual number of ions Determine the individual number of ions To get 6 total positives you need 3 barium ions To get 6 total positives you need 3 barium ions To get 6 total negatives you need 2 phosphate ions To get 6 total negatives you need 2 phosphate ions Write the formula with those numbers Write the formula with those numbers Ba 3 (PO 4 ) 2 Ba 3 (PO 4 ) 2

Writing Ionic Formulas Write the formula of the following Write the formula of the following A compound made from aluminum and hydroxide ions. A compound made from aluminum and hydroxide ions. A compound made from magnesium and sulfur. A compound made from magnesium and sulfur. A compound made from strontium and nitrite ions. A compound made from strontium and nitrite ions.

Naming Ionic Compounds Based on you already knowing the charges of the ions involved. Based on you already knowing the charges of the ions involved. Does not tell you how many of each ion there are. Does not tell you how many of each ion there are.

The Rules Name the positive ion first Name the positive ion first Na + = sodium ion Na + = sodium ion (Leave a couple lines of blank space here) (Leave a couple lines of blank space here) Name the negative ion last Name the negative ion last Change the name of a monatomic anion to have an –ide ending. Change the name of a monatomic anion to have an –ide ending. Polyatomic ions names are not changed Polyatomic ions names are not changed

Practice Problems Name the following: Name the following: BaCl 2 BaCl 2 MgO MgO Na 3 P Na 3 P Al 2 (SO 4 ) 3 Al 2 (SO 4 ) 3

Those Stupid d-Orbitals Consider the following copper oxides: Consider the following copper oxides: CuO Cu 2 O Determine the charge on the copper ions in both compounds.

Multi-valent metals Most metal ions can have multiple stable charges because of the d-orbitals. Most metal ions can have multiple stable charges because of the d-orbitals. The ones that can’t are: The ones that can’t are: Group 1 Group 1 Group 2 Group 2 Silver (+1) Silver (+1) Zinc (+2) Zinc (+2) Aluminum(+3) Aluminum(+3) For everything that can have a multiple charge you must specify the charge in the name. For everything that can have a multiple charge you must specify the charge in the name. Use Roman numerals to tell the charge. Use Roman numerals to tell the charge.

The Rules Name the positive ion first Name the positive ion first Na + = sodium ion Na + = sodium ion Specify the charge of all metal ions with a Roman numeral Specify the charge of all metal ions with a Roman numeral Except Group 1, Group 2, Ag, Zn, Al Except Group 1, Group 2, Ag, Zn, Al Name the negative ion last Name the negative ion last Change the name of a monatomic anion to have an –ide ending. Change the name of a monatomic anion to have an –ide ending. Polyatomic ions names are not changed Polyatomic ions names are not changed

Those Stupid d-Orbitals CuO Cu 2 O Name the compounds above: Name the compounds above: Black = copper(II) oxide Black = copper(II) oxide Red = copper(I) oxide Red = copper(I) oxide Remember the Roman numeral is the charge not the number of atoms. Remember the Roman numeral is the charge not the number of atoms.

Practice Problems Name the following compounds Name the following compounds Fe 2 O 3 Fe 2 O 3 Co(NO 3 ) 2 Co(NO 3 ) 2 CaCO 3 CaCO 3 NH 4 C 2 H 3 O 2 NH 4 C 2 H 3 O 2

Practice Problems Name the following compounds Name the following compounds MnO 2 MnO 2 AgCl AgCl CrN 2 CrN 2 W 2 O 5 W 2 O 5

Practice Problems Write the formulas for the following compounds: Write the formulas for the following compounds: Tin(IV) oxide Tin(IV) oxide Aluminum chloride Aluminum chloride Ammonium sulfide Ammonium sulfide

Practice Problems Write the formulas for the following compounds: Write the formulas for the following compounds: Potassium dichromate Potassium dichromate Chromium(II) nitrate Chromium(II) nitrate Technetium(VII) oxide Technetium(VII) oxide