1. Compounds and their Bonds
Ionic Bonds &
Naming Ionic Compounds

2. REVIEW
The group your element is in, determines the number of valence electrons
How do you use the Periodic Table to determine the number of valence electrons for a given element?

3. REVIEW: Lewis Electron Dot Structure
Symbols of atoms with dots to represent the valence-shell electrons
1A A A A A A A A
H He
Li Be B C N O F Ne
Na Mg Al Si P S Cl Ar

4. LEARNING CHECK A. X would be the electron dot formula for
1) Na 2) S 3) Al
 
B  X  would be the electron dot formula for 
1) B 2) N 3) Cl

5. CHEMICAL BONDS: Why do atoms form bonds?
Atoms are stable when they have 8 valence electrons
They fulfill the Octet Rule
There is always an exception:
Hydrogen and Helium
Hydrogen only needs one more electron to fill its valence shell
Helium is full with its 2 valence electrons therefore does not bond
Atoms can fulfill the Octet Rule when they gain, lose or share electrons

6. Octet Rule = atoms tend to gain, lose or share electrons so as to have 8 electrons
C would like to
N would like to
O would like to
Gain 4 electrons of lose 4 electrons
Gain 3 electrons
Gain 2 electrons

7. CHEMICAL BONDS: What types of bonds are there?
Ionic Bonds
Covalent Bonds
Metallic Bonds
Hydrogen Bonds

8. What is an ion?
An ion: an atom or bonded group of atoms with a positive or negative charge
Cation: A positively charged ion
Anion: A negatively charged ion + -

9. IONIC BONDS Group 1A metals  ion 1+ Group 2A metals  ion 2+
Bonds formed between 2 ions by the transfer of electrons
Result when a metal reacts with a non-metal
Metals lose electrons (transfer e- to the non-metal) to match the number of valence electrons of their nearest noble gas
Positive ions (CATIONS) form when the number of electrons are less than the number of protons
Group 1A metals  ion 1+
Group 2A metals  ion 2+
Group 3A metals  ion 3+
+ means it has more protons

10. LEARNING CHECK 1. Number of valence electrons in aluminum
A) 1 e B) 2 e- C) 3 e-
2. Change in electrons for octet
A) lose 3e B) gain 3 e C) gain 5 e-
3. Ionic charge of aluminum
A) B) C) 3+

11. SOLUTION 1. Number of valence electrons in aluminum C) 3 e-
2. Change in electrons for octet
A) lose 3e-
3. Ionic charge of aluminum
C) 3+

12. IONIC BONDS
Non-metals in groups 5A, 6A, and 7A gain electrons from the metals
Non-metals:
Accept electrons from the metal
Gain electrons
Negative ions (ANIONS) form when the number of electrons is more than the number of protons
Group 5A metals  ion 3-
Group 6A metals  ion 2-
Group 7A metals  ion 1-
- Means less protons

13. LEARNING CHECK Number of valence electrons in Oxygen
A) 5 e- B) 6 e- C) 7 e-
Change in electrons for octet
A) gain 2 e- B) lose 2 e- C)gain 4 e-
Ionic charge for Oxygen
A) 2+ B) +4 C) 2-

14. SOLUTION Number of valence electrons in Oxygen B) 6 e-
2. Change in electrons for octet
A) gain 2 e-
Ionic charge for Oxygen
C) 2-

15. IONIC BONDS Properties High Melting point and Boiling Point
Conductors of electricity Strong bonds; stronger than covalent bonds
Bond by transfer electrons

16. REVIEW: IONIC BOND
an electron is simply transferred to another atom. By doing so, each atom is able to have a stable valence shell. It is called an ionic bond because the atoms become ions, a charged atom that has either lost an electron (positive charge) or has gained an electron (negative charge). Below is an animation of ionic bonding:

17. WRITING IONIC COMPOUNDS
Write each ion, cation first
Don’t show charges in the final formula.
Overall charge must equal zero.
Use parentheses to show more than one polyatomic ion.
Stock System –
Roman numerals indicate the ion’s charge
used when the ion has more than one oxidation state (Transition elements)
Copyright © by Pearson Education, Inc.

18. Polyatomic ion NO3 goes in parentheses
Calcium Nitrate
Ca NO3-1
Ca1(NO3)2
Ca (NO3)2
1(+2) + 2(-1)= 0
EXAMPLE:
Cross the exponents only! not the + or -
Do NOT show 1 in the final formula
Polyatomic ion NO3 goes in parentheses
This is your final formula!
Check for the overall charge to equal zero

19. LEARNING CHECK potassium chloride magnesium nitrate
copper(II) chloride
K+ Cl-
 KCl
Mg2+ NO3-
 Mg(NO3)2
Cu2+ Cl-
 CuCl2

20. NAMING IONIC COMPOUNDS
Identify the cation and anion
Name the cation first
Name the anion with an –ide ending

21. Learning Check
Complete the names of the following ions: (Is it a cation or an anion?)
Ba2+ Al3+ K+
_________ __________ _________
N3 O2 F
_________ __________ _________

22. Solution Ba2+ Al3+ K+ barium aluminum potassium N3 O2 F
nitride oxide fluoride

23. Examples of Ionic Compounds with Two Elements
Formula Ions Name
cation anion
NaCl Na+ Cl- sodium chloride
K2S K S2- potassium sulfide
MgO Mg2+ O2- magnesium oxide
CaI Ca2+ I- calcium iodide
Al2O3 Al O2- aluminum oxide

24. Learning Check Write the names of the following compounds:
1) CaO ___________
2) KBr ___________
3) Al2O3 ___________
4) MgCl2 ___________

25. Solution Write the names of the following compounds:
1) CaO calcium oxide
2) KBr potassium bromide
3) Al2O3 aluminum oxide
4) MgCl2 magnesium chloride

26. Metals That Form More Than One Cation
The name of metals with two or more positive ions (cations) use a Roman numeral to identify ionic charge.

27. Naming Ionic Compounds with Variable Charge Metals

28. Naming Variable Charge Metals
Transition metals with two different ions use a Roman numeral after the name of the metal to indicate ionic charge.

29. EXAMPLE: Naming FeCl2 To name FeCl2:
1. Determine the charge of the cation using the subscript of the anion (Cl-).
Fe ion = 2+
2. Name the cation by the element name and add a Roman numeral in parentheses to show its charge.
Fe2+ = iron (II)
3. Write the anion with an ide ending.
FeCl2 = iron(II) chloride
Remember Iron is a Transition metal which is the reason for the Roman numeral

30. Learning Check Select the correct name for each. 1. Fe2S3
A) iron sulfide
B) iron(II) sulfide
C) iron(III) sulfide
2. CuO
A) copper oxide
B) copper(I) oxide
C) copper(II) oxide

31. Solution Select the correct name for each. A. Fe2S3
C) iron (III) sulfide Fe3+ S2-
B. CuO
C) copper (II) oxide Cu2+ O2-