Writing formulas for multivalent ionic compounds Transition metals have the ability to form more than one cation Therefore, a roman numeral is placed in the name to signify the charge on the cation Example: –Iron (III) Chloride Write the formula? Transition metals have the ability to form more than one cation Therefore, a roman numeral is placed in the name to signify the charge on the cation Example: –Iron (III) Chloride Write the formula?

Writing formulas for mulitvalent ionic compounds Write formulas for the following: Copper (I) Oxide Copper (II) Oxide Answers - Cu 2 OCuO Write formulas for the following: Copper (I) Oxide Copper (II) Oxide Answers - Cu 2 OCuO

Naming compounds with multivalent metals If the metal is in group B it requires a roman numeral in the name. You will have to deduce the roman numeral based on the formula. Example –Name CoI 2 Answer - Cobalt (II) Iodide If the metal is in group B it requires a roman numeral in the name. You will have to deduce the roman numeral based on the formula. Example –Name CoI 2 Answer - Cobalt (II) Iodide

Naming compounds with multivalent metals Deducing the roman numeral Multiply the charge on the anion by the number of anions and then divide by the number of cations to get the roman numeral. Write the names for Fe 2 S 3 SnO 2 Answers - –Iron (III) SulfideTin (IV) Oxide Deducing the roman numeral Multiply the charge on the anion by the number of anions and then divide by the number of cations to get the roman numeral. Write the names for Fe 2 S 3 SnO 2 Answers - –Iron (III) SulfideTin (IV) Oxide

Take ten minutes and work on sections 5 and 6 on the back side of your worksheet.

Polyatomic Ions A group of atoms that carry a charge Examples: –SO 4 2- NO 3 1- Names of polyatomic ions that contain oxygen will end in -ate or -ite -ite is one less oxygen then ate Example –Sulfate is SO 4 2- Sulfite is SO 3 2- –Chlorate is ClO 3 1- Chlorite is ClO 2 1- Other polyatomic ions –NH 4 1+ Ammonium CN 1- cyanide –OH 1- Hydroxide A group of atoms that carry a charge Examples: –SO 4 2- NO 3 1- Names of polyatomic ions that contain oxygen will end in -ate or -ite -ite is one less oxygen then ate Example –Sulfate is SO 4 2- Sulfite is SO 3 2- –Chlorate is ClO 3 1- Chlorite is ClO 2 1- Other polyatomic ions –NH 4 1+ Ammonium CN 1- cyanide –OH 1- Hydroxide

Writing formulas using polyatomic ions The polyatomic ion is treated as one unit. Balance the charges Place parenthesis around the polyatomic ion if there is more than one Example –Write the formula for Iron (II) Nitrate Fe 2+ and NO 3 1- combines to make Fe(NO 3 ) 2 The polyatomic ion is treated as one unit. Balance the charges Place parenthesis around the polyatomic ion if there is more than one Example –Write the formula for Iron (II) Nitrate Fe 2+ and NO 3 1- combines to make Fe(NO 3 ) 2

Naming using Polyatomic ions Name the metal than name the polyatomic ion. If you need a roman numeral; include it. Treat the polyatomic ion as one unit (as if it were one atom) Example - Name CuSO 4 Copper (II) Sulfate Name the metal than name the polyatomic ion. If you need a roman numeral; include it. Treat the polyatomic ion as one unit (as if it were one atom) Example - Name CuSO 4 Copper (II) Sulfate

Exceptions for roman numerals Silver, Cadmium and Zinc do not get roman numerals. Ag is always +1, Cadmium and Zinc are always +2 Tin and Lead need roman numerals. They are multivalent (multiple oxidation states) Silver, Cadmium and Zinc do not get roman numerals. Ag is always +1, Cadmium and Zinc are always +2 Tin and Lead need roman numerals. They are multivalent (multiple oxidation states)

Naming Acids Memorize HCl - Hydrochloric Acid H 2 SO 4 - Sulfuric Acid HNO 3 - Nitric Acid H 3 PO 4 - Phosphoric Acid Note - Acids give off H 1+ (Hydrogen ions) and bases give off OH 1- ions What do you get when an acid and base combine? Memorize HCl - Hydrochloric Acid H 2 SO 4 - Sulfuric Acid HNO 3 - Nitric Acid H 3 PO 4 - Phosphoric Acid Note - Acids give off H 1+ (Hydrogen ions) and bases give off OH 1- ions What do you get when an acid and base combine?

Check for understanding Name or write the formula for: –Potassium Sulfate –Chromium (III) Cyanide –Fe(ClO 3 ) 3 –CuCl Answers –K 2 SO 4 Cr(CN) 3 –Iron (III) Chlorate –Copper (I) Chloride Name or write the formula for: –Potassium Sulfate –Chromium (III) Cyanide –Fe(ClO 3 ) 3 –CuCl Answers –K 2 SO 4 Cr(CN) 3 –Iron (III) Chlorate –Copper (I) Chloride

Now finish your worksheet and work on your homework. Get help Make sure and check your answers on- line. You will be writing formulas all year and doing math based on these formulas. You get the formula wrong you get the math wrong. Now finish your worksheet and work on your homework. Get help Make sure and check your answers on- line. You will be writing formulas all year and doing math based on these formulas. You get the formula wrong you get the math wrong.