1. Unit 5 Nomenclature and Bonding
Chemistry

2. Bonding What is a chemical bond?
The attractive force that holds two or more atoms together
What are the 3 main types of bonds?
Ionic
Covalent
Metallic

3. IONIC BONDS & COMPOUNDS
Formula Unit- an ionic compound written in its simplest ratio
Ionic compound- a compound (metal + nonmetal) that is held together by ionic bonds
Involves a transfer of electrons
a metal ( cation) & a nonmetal ( anion)
Metal gives away; nonmetal accepts
Ex: Na =
Cl =
Forms NaCl, an ionic compound

4. Practice Which of the following would form ionic compounds?
chromium and oxygen
nitrogen and hydrogen
phosphorus and oxygen
barium and sulfur
tin and fluorine
carbon and nitrogen

5. 11/2 warm-up What is an ionic bond?
If you gain electrons you will become?
If you lose electrons you will become?
Cation=
Anion=

6. These ionic compounds are stable because they transfer electrons to have a full valence shell
(cation loses e- while the anion gains e-)
Properties of ionic compounds:
Solid
High MP
m + nm
Can only conduct electricity when dissolved in water (called an electrolyte)

7. Predicting Formulas of Ionic Compounds
Just criss cross the charges (use the Periodic Table to get the charges)
Ex: 2 Na+1 + O-2  Na2O
* Ionic bonds
metal + oxygen = “oxide”
ex: Ca+2 + O-2  CaO, calcium oxide
metal + halogen = “salt”
ex: Ca+2 + Cl-1  CaCl2, a chloride salt

8. Predicting the Formula
Write the formula for the compound formed between potassium and sulfur
1. Determine and write the chemical symbol and oxidation number for each element
2. Criss Cross the charge #s. The sum of the charges must = 0. If they are both the same subscript, they cancel out to be 1.
What does the subscript tell you?

9. Predicting the Formula
Now try aluminum and chlorine
What about magnesium and oxygen?
Another rule: when the subscripts are the same, you can simplify them down

10. 11/3 warm-up What does binary mean?
Which comes first when writing the formula for ionic compounds, the non metal or the metal?
Write the formula for aluminum and chlorine.

11. General Nomenclature Rules
1. Is the compound binary? (2 elements only)
Yes Go to #2
No  Go to #5
2. Is one element a metal?
Yes Go to #4
No  Go to #3
3. Are both elements non-metals?
Yes use prefixes for the # of atoms
No  Go back to #2…
Ex: CO2 is carbon dioxide (the prefix “mono” is NEVER used with the 1st element!)

12. Nomenclature Rules- cont.
4. Is it a transition metal / p-block metal?
Yes use a Roman numeral to specify its charge
Ex: CuO is copper (II) oxide
No  name the metal first, then change the ending of the nonmetal to “ide”
Ex: Li2O is lithium oxide
5. Is it a transition metal / p-block metal?
Ex: CuSO4 is copper (II) sulfate
No  name the metal then add the polyatomic ion name
Ex: Na2SO4 is sodium sulfate
1 mono hexa-
2 di hepta-
3 tri octa-
4 tetra nona-
5 penta- 10 deca-

13. practice
MgS
KBr
Ba3N2
Al2O3
NaI
SrF2

14. Transition Metals Write the formula for the following:
Copper (I) iodide
Copper (II) iodide
Chromium (II) fluoride
Chromium (III) fluoride
Write the name for the following:
CrF3
CrO
Cr2O3
Cr3P2
CrP

15. Transition Metal Ions Exceptions
silver is always Ag1+
cadmium (Cd) & zinc (Zn) are always2+

16. 11/8 warm-up before quiz Sodium Bromide Copper (II) chloride
Calcium oxide
Tin (IV) sulfide
Rb2O
CuCl
PbS

17. 11/10 warm-up Finish your lab
Pairs finish the descriptions AND the formulas on the back
Then in your group of 4 answer the pre and post lab questions
Put in the bin when you are done

18. Compound Nomenclature
Binary compound
yes no
Use Acid naming rules
Is hydrogen the cation?
Is hydrogen the cation?
yes
yes no no
Metal present
Polyatomic ion
or ions present? no no
yes
Not established
yes
Use prefixes; “ide” ending
Can the metal form more than one charge?
Just name the polyatomic ion no
yes
Just name the elements;
the anion ends in “ide”
Name the metal with a Roman numeral to designate its charge; the anion ends in “ide”

19. Polyatomic Ions
Polyatomic Ionic Compounds: ionic compounds that contain polyatomic (more than 2) ions
To write:
Always write metal or + ion 1st
Criss Cross the charges
**If the charge of the metal ion is higher than 1, use ( ) around the polyatomic ion formula before writing that subscript
Ex: Ca(NO3)2

20. 11/28 warm-up What is an ionic bond?
What electrons are used during ionic bonds?
What is a cation?
What is an anion?
Remember to have these prefixes in your notes somewhere:
1 mono hexa-
2 di hepta-
3 tri octa-
4 tetra nona-
5 penta- 10 deca-

21. Common Mistakes
Not KNOWING the 14 polyatomics – correct formula and charges
Not KNOWING the charges of elements based on the periodic table.
Alkali metals are 1+, alkaline earth metals are 2+, aluminum is 3+, nitrogen group is 3-, oxygen group is 2-, halogens are 1-.
Transition metals (except zinc, cadmium, and silver) and metals in the P block have more than 1 charge.
Not putting the parentheses around hydroxide when there is more than 1.
OH2 is water; (OH)2 is 2 hydroxides
Not simplifying (if the charges are the same, no subscripts are needed)
Not using roman numerals correctly in the names.

22. 11/29 warm- up
How can you tell the difference between a covalent and ionic bond?
What type of bond for the following?
CO2
CaCl2
C6H12O6

23. 11/13 warm-up
Complete 1-10 on the front and
then 21-30

24. On your poster: Definition in your own words Examples
Drawing that describes your definition

25. Vocabulary poster Chemical Bond Electrolyte Formula unit Cation
Monoatomic ion
Anion
Ionic bond
Oxidation number
Ionic compound
Polyatomic ion

26. 11/27 warm-up How is an ionic bond formed?
What holds the ions together in the solid form?
If we dissolve the solid ions in water what can we do with that solution?

27. COVALENT BONDS
Covalent Bond- a bond formed by sharing valence electrons
nm + nm (made up of nonmetals only)
Nonmetallic; Low MP; Can be solid, liquid, or gas
FORM Molecules = smallest neutral unit of a covalently bonded substance
(“co” = to share)
Ex: co-ed, cooperation

28. COVALENT COMPOUND NOMENCLATURE
1) Name 1st element in formula using the entire element name
2) Name 2nd element in formula using the root of the element name with the suffix –ide
3) Prefixes are used to indicate the #of atoms of each type that are present
1 mono- 6 hexa-
2 di hepta-
3 tri octa-
4 tetra- 9 nona-
5 penta- 10 deca-
NEVER use mono in the name of the 1st element

29. COVALENT NOMENCLATURE PRACTICE
Ex: P2O5 is diphosphorus pentoxide
Notice that the ‘a’ on penta was dropped because oxide started with a vowel
Name the following:
NF3, SO2, CO2
Write the formula for the following:
Diarsenic Trioxide
Carbon Monoxide
Carbon TetraChloride
There are some common names for covalent compounds
Formula common name molecular name
H2O water dihydrogen monoxide
NH3 ammonia nitrogen trihydride
N2O nitrous oxide dinitrogen monoxide
(laughing gas)

30. 2. Covalent
Molecule
Share e-
Nonmetallic
Solid, liquid or gas
Low solubility in water
High to Low MP, BP<300C
Poor to non-conductivity
All diatomic

31. 11/28 warm-up What is a covalent bond?
Write two examples of covalent bonds.

32. Reminders ALL ATOMS WANT 8 or an octet They want 8 for STABILITY!!!
Except H wants 2!
They want 8 for STABILITY!!!
High Stability = Low energy

33. *Atoms bond to achieve a stable valence electron configuration
Show arrangement using Lewis Dot Structures:
1)  Write symbol
2)Using dots show the number of valence e-
3)Connect single dots together between atoms

34. EX: CH4 C2H6 C2H4 •• F F single bond – each shares 1 e-
(each F shares 1 e-)
N shares 3 e- , each H shares 1 e- N
H H H
EX: CH4 C2H6 C2H4

37. Single Covalent Bond- share 2 e-; 1 pair
Ex:H2, F2, Cl2, Br2, I2, O2, N2,
Diatomnic Molecules ^: they are too unstable to be alone
Double Covalent Bond- share 4 e-; 2 pair EX- O2, CO2
Triple Covalent Bond- share 6 e-; 3 pair EX- N2
 Group 4A shares 4 e-
Group 5A shares 3 e-
Group 6A shares 2 e-
Group 7A shares 1e-

38. 11/29 warm-up What is the name of SCl4
What is the formula for Antimony tribromide?
Draw the lewis structure for antimony tribromide
Draw the lewis structure for Hyrogen iodide
Draw the lewis structure for N2

39. Bond strength
Single bond: 1 sigma bond; weakest because it has longest bond length
Double bond: 1 sigma bond and 1 pi bond
Triple bond: 1 sigma bond and 2 pi bonds; shortest so it is the strongest

40. C. Warm-up: Fill in Comparison Chart
IONIC
COVALENT
transferred from metal to nonmetal
shared between nonmetals
Electrons
Melting
Point
high
low
Soluble in
Water
yes
usually not
yes (solution or liquid)
Conduct Electricity no
crystal lattice of ions, crystalline solids
molecules, odorous liquids & gases
Other
Properties

41. 12/1 warm-up Write the name of the following:
Ag3PO4
K4C
Ag3N
NiO2
Write the formula for the following:
Ammonium carbide
Draw the lewis dot diagram for O2. How many electrons are shared?
Draw the lewis dot diagram for N2. How many electrons are shared?

42. Metallic & Nonmetallic Solid High Solubility in water
2. Covalent
Molecule
Share e-
Nonmetallic
Solid, liquid or gas
Low solubility in water
High to Low MP, BP<300C
Poor to non-conductivity
All diatomic, H2O, CH4, CO2
1. Ionic
Formula unit
Transfer e-
Metallic & Nonmetallic
Solid
High Solubility in water
High BP, MP >300C
Good conductor in solution
NaCl, KBr, CaCO3

43. Summary Ionic, & Covalent Compounds
Compare and Contrast
Summary Ionic, & Covalent Compounds

44. Summary Ionic, & Covalent Compounds
Oppositely charged ions attracted to each other (cations and anions)
Metals with non-metals
Brittle, dull solids
Only conducts electricity as electrolytes
Generally, medium MP of 3 types
Covalent
Sharing of electrons
Non-metals with non-metals or metalloids with non-metals
Polar and nonpolar compounds
Generally do not conduct electricity
Lowest MP of the 3 types
All bonding involves valence electrons
Includes non-metals

45. 12/4 warm-up
Get with a partner and work on the molecular geometry worksheet. DO NOT TRY TO FILL IN THE TABLE. Go straight to number one on the back of the first sheet.

46. 12/5 warm-up Turn in your homework
What is electronegativity? LOOK IN YOUR NOTES!!!!
Ionic bonds do what with their electrons?
Covalent bonds do what with their electrons?

47. Bond Type, EN and Polarity
EN: ability to pull e- when bonded
(units are “Paulings”)
Ionic compounds – do not share e-, but transfer completely
Polar covalent compounds – share e- unevenly
When shared unevenly, there is an e- shift providing a “partial” charge. The more EN end of molecule is -; the end that “lost” e- is +
H – Cl: Cl is more EN, so it would be the partially negative end
Nonpolar covalent compounds – share e- evenly

48. EN & Bond Type Look up values on pg 194 and get difference
Non-polar Covalent Bonds- bonding e- are shared evenly EN difference below 0.4
Polar Covalent Bonds- e- shared unevenly; EN difference between 0.4 & 2.1
Polar molecule- one end of molecule is - & the other end is +
Also called dipole- place it on magnetic field & it will orient to the poles
Ionic compounds- have an EN difference above 2.1

49. Polar or Nonpolar?
A molecule will be polar when there are lone pairs of e- remaining unbonded on the central atom (don’t count lone pairs of e- on outside atoms)
All other molecules will be nonpolar
Ex: CO2, NH3, BF3

50. Types of Intermolecular Forces
What makes molecules strong and held together?
3 Types of Intermolecular Forces (attractions between molecules)
* 1. Dispersion- (e- shifts in molecules)
Usually large atoms or molecules
Weakest
* 2.Dipole Forces- polar molecules attracted to one another
Moderate

51. *3. H-Bonding- not an actual bond, when molecules containing H with F, O, or N are attracted to one another 
Strongest of all intermolecular forces
Types of bonding between molecules determines physical properties of compound
Higher IM forces= higher MP & BP= More solid

52. 12/7 warm-up Check your quiz answer: 12 a 1 a 13 d 2 a 14 b 3 a 15 d

53. 12/12 warm-up Turn in crossword puzzles to bin
What electronegativity values would a metal have? Non metal?
Is PCl3 a polar or non polar molecule? Why?