1. 9-1 Notes
Naming Ions

2. Monatomic Ions
Ionic compounds consist of a positive ion (a metal) bonded to a negative ion (a nonmetal)
Ex. KBr
Monatomic ions consists of a single atom that has lost or gained electron(s)
Ex. Potassium ion lost an electron, while the Bromide ion gained an electron

3. Cations
Cations are positively charged ions that occur when atoms lose electrons
The # of electrons lost will correspond to the group # on the periodic table
Ex. Sodium in group 1 will lose 1 electron
Naming Cations – the name is the same as the element the ion is formed from
Ex. Sodium forms the sodium cation
Identify the cation of the following elements: Ca, Rb, Al, Li, Sr

4. Anions
Anions are negatively charged ions that occur when atoms gain electrons
Nonmetals in groups 5-7 form anions
The charge is determined by subtracting 8 from the group #
Ex. Oxygen is in group 6, therefore, 6-8 = -2
Naming Anions – the end of the element’s name changes to –ide
Ex. Bromine forms the Bromide anion
Identify the anions of the following elements: P, Se, I, F, N

5. Ions of Transition Metals
Many of the transition metals form more than 1 cation
The charges must be determined from the number of electrons lost
Ex. Iron can lose 2 electrons and form Fe2+ or it can lose 3 electrons and form Fe3+
See Table 9.2 p. 255

6. Ions of Transition Metals
There are 2 ways to name these ions
1. Stock System – uses roman numerals to indicate the charge on the ion
Ex. Fe2+ is Iron (II) while Fe3+ is Iron (III)
2. Classical name – uses the Latin form of the element and a suffix to indicate the charge
The suffix –ous indicates the lower of the 2 charges
The suffix –ic indicates the higher of the 2 charges
Ex. Fe2+ is the ferrous ion while Fe3+ is the ferric ion
A few transition metals only form 1 ion and these are named like all other cations
Ex. Silver (Ag+), Zinc (Zn2+)

7. Polyatomic Ions Polyatomic ions are composed of more than 1 atom
Ex. Nitrate (NO3-) consists of both nitrogen and oxygen
The names of most polyatomic ions end in -ite or –ate
The use of –ite or –ate as the ending usually depends on the # of Oxygen atoms in the ion
Ex. Nitrate (NO3-) has more oxygen atoms while Nitrite (NO2-) has less oxygen atoms

8. Polyatomic Ions
If the formula for a polyatomic ion begins with an H it includes a H+
The charge is the sum of the two ions
Ex. Hydrogen carbonate (HCO3-) is the sum of H+ and CO32-
Most polyatomic ions are negatively charged
The 1 exception is NH4+ which is ammonium
See Table 9.3 p. 257

9. Naming and Writing Formulas for Ionic Compounds
9-2 Notes
Naming and Writing Formulas for Ionic Compounds

10. Naming Binary Ionic Compounds
A binary compound is composed of 2 elements and can either be ionic or molecular
1st step in naming an ionic compound is making sure it is composed of a monatomic metal cation and a monatomic nonmetal anion
When naming, simply place the cation name first followed by the anion name
Ex. KBr is Potassium bromide, while Na2O is sodium oxide
When the cation is a transition metal with more than 1 charge, you must indicate which ion is being used
Ex. Cu2O is Copper (I) oxide, while CuO is Copper (II) oxide

11. Writing Formulas for Binary Ionic Compounds
Step 1: Write the symbol of the cation and then the anion.
Step 2: Add whatever subscripts are needed to balance the charges
Make sure the subscripts are reduced
There are two methods to balance charges
1. Find the least common multiple of the charges
2. The crisscross method: the numerical value of the charge of each ion is crossed over and becomes the subscript for the other ion
Write the formulas for the following: Iron (III) oxide and Calcium bromide

12. Compounds with Polyatomic Ions
Naming ionic compounds with polyatomic ions is the same as binary compounds
Write the cation first followed by the anion
Name the following: LiCN, AgNO3, (NH4)2C2O4

13. Compounds with Polyatomic Ions
Step 1: Write the symbol of the cation and then the anion.
Step 2: Add whatever subscripts are needed to balance the charges
Step 3 (if needed): If more than 1 polyatomic ion is needed to balance the charges you must use parentheses
Ex. Calcium Nitrate
Write the formulas for the following: Lithium carbonate & Aluminum nitrite

14. Naming and Writing Formulas for Molecular Compounds
9-3 Notes
Naming and Writing Formulas for Molecular Compounds

15. Review How do we do the following? Name Ionic Compounds
Ex. KBr, Na3PO4, Fe(NO3)3
Write Formulas for Ionic Compounds
Ex. Sodium nitride, Ammonium oxide, Copper (II) nitrite

16. Naming Binary Molecular Compounds
Binary molecular compounds are composed of molecules, not ions, and consist of 2 nonmetals
Due to various ways of sharing electrons the same elements can be used to make different compounds
Ex. CO and CO2
How do you name these so you can tell there is a difference?

17. Naming Binary Molecular Compounds
Prefixes are used to represent the number of atoms of each element that can be found in a molecular compound
The Rules:
1. Confirm the compound is molecular
2. Name the elements in the order listed in the formula
3. Use the appropriate prefix to indicate the # of each element (see table 9.4 p. 269)
Exception: Do not use mono- on the 1st element
4. Change the ending of the 2nd element to –ide
Name the following: CO, CO2, N2O5, CCl4

18. Writing Formulas for Molecular Compounds
Step 1: Write the correct symbols for the two elements
Step 2: Use the prefixes in the name to determine the subscript of each element in the formula
Write the formula for the following: Dinitrogen tetraoxide, Dihydrogen monoxide, Phosphorus pentachloride

19. Naming and Writing Formulas for Acids and Bases
9-4 Notes
Naming and Writing Formulas for Acids and Bases

20. Review How do we do the following? Write Formulas for Ionic Compounds
Name Ionic Compounds
Ex. (NH4)3PO4, Cr(NO2)3
Write Formulas for Ionic Compounds
Ex. Potassium sulfate, Iron (III) oxide
Name Molecular Compounds
Ex. CO2, CCl4
Write Formulas for Molecular Compounds
Ex. Boron Trichloride, Dinitrogen tetrahydride

21. Naming Acids
An acid is a compound that contains 1 or more hydrogen atoms and produces H+ when dissolved in water
The general form of an acid is HnX
n is the subscript indicating how many Hydrogen ions are needed
X is the monatomic or polyatomic anion

22. Naming Acids – The Rules
1. If the anion ends in –ide, the acid name will begin with hydro-. The –ide will be replaced by –ic and followed by acid
Ex. HCl
2. If the anion ends in –ite, the acid name is the stem of the anion with the suffix –ous and followed by acid
Ex. H2SO3
3. If the anion ends in –ate, the acid name is the stem of the anion with the suffix –ic and followed by acid
Ex. HNO3
Name the following: HF, HNO2, HMnO4

23. Writing Formulas for Acids
Use the rules for writing the names of acids in reverse to write the formulas for acids
Remember – add subscripts to balance the formula
Ex. Rule 1 – Hydrobromic acid
Ex. Rule 2 – Phosphorous acid
Ex. Rule 3 – Sulfuric acid
Write formulas for the following: Permanganic acid, Nitrous acid, hydrosulfuric acid

24. Bases
A base is an ionic compound that produces hydroxide ions when dissolved in water
Naming bases and writing formulas is the same as any other ionic compound
Name the following: Ba(OH)2, KOH
Write the formulas for the following: Strontium hydroxide, Copper (II) hydroxide