1. Covalent Compounds (molecules)
Agenda: 10/23
Homework:
Warm-up: Ionic Bonds
Ionic Compounds – names & formulas
Binary
With Roman numerals
With 3 or more elements
Covalent Compounds (molecules)

2. Ionic Bonds (Black Study Guide)
Read

3. Usually need high heat or electricity
Compounds
Stable (do not easily change)
Most atoms are bonded into compounds
Separated with chemical reactions
Usually need high heat or electricity

4. Metals lose valence electrons Non-metals gain valence electrons
Ionic Compounds
Metals lose valence electrons
Non-metals gain valence electrons

5. Ionic Bonding: Transfer of valence electrons
Ionic bonding occurs when a metal loses 1+ electrons to a non-metal in an effort to attain a stable octet of valence electrons.
Use Electron Dot Diagrams (Lewis diagrams) to show the ionic bonds for one formula unit.
Na Cl = Na⁺¹Cl⁻¹

6. Electron Dot Diagram (Lewis)
Cl Ca Cl
= Ca Cl

7. Ionic Compounds
Names and Formulas

8. Language of chemistry: Standardize system to represent compounds
Inorganic Compounds
Ionic
M & NM
With Roman numeral
3 or more elements
Covalent (molecules)
NM & NM
Diatomic Molecules
Acids

9. Inorganic Compounds Ionic Covalent (molecules)
Binary - representative metals
Formulas
Names
Transition & post transition metals
Polyatomic ions
Covalent (molecules)
Binary
Diatomic molecules
Acids

10. Ionic Compounds

11. Ionic compounds: Found in minerals and rocks
Granite: rock (combination of minerals)

12. Halite: NaCl
Use as source of table salt

13. Ionic compounds: rocks & minerals
Al₂O₃
Aluminum oxide

14. Pyrite (Fool’s gold) Iron sulfide FeS₂
Used to produce sulfuric acid for the chemical industry

15. Ionic Compounds - Opposites Attract
Separate cations and anions to bond
Use only the single element ions (not the polyatomic ions)
Write the symbol and the charge
Write the new compound formed by combining the ions. Write the formula showing that the charges (oxidation numbers) add up to 0 (cancel out)
Name the compound.
Write at least 15 compounds.
Ten should include subscripts.

16. Ionic Compounds: Names & Formulas
The formula for ionic compounds are determined by the charges (oxidation numbers). The overall charge of the compound must equal 0.
The charges are determine by the number of valence electrons that the element loses or gains to reach 8 valence electrons. This is the octet rule that makes the compound stable (does not easily react.)

17. c. Metals always _______ electrons to form a ____ ion
c.Metals always _______ electrons to form a ____ ion. Non-metals always _______ electrons to form a ______ ion .
Group 1 2 13 14 15 16 17 18
Charge =
Oxid. #

18. e. Since Aluminum has a charge (oxidation number) of 3⁺, - It must have __________ chlorine atoms (ions) to make a stable compound. -It must have __________ nitrogen atoms (ions) to make a stable compound. -It must have _______ aluminum and ________ oxygen atoms (ions) to make a stable compound.

19. Write the correct formula for compounds composed of:
Sodium and bromine Sodium and sulfur Sodium and phosphorus
Calcium and bromine Calcium and sulfur Calcium and phosphorus

20. Names for Ionic compounds
Rules for naming:
Metals are written first.
Non-metals change their name to an “-ide” ending.
Prefixes are ________ ___________.

21. Ionic Compounds- Formulas
Salt is a commonly
used term for all ionic compounds

22. Some Ionic Compounds are more complex
Include polyatomic ions

23. Ionic compounds: Found in minerals and rocks
Barite = BaSO₄
Used to make paper & glass
Source of barium used
For x-rays of the digestive
system

24. Ionic compounds: Found in minerals and rocks
Gypsum = CaSO₄· 2H₂O
Used for plaster for
walls, ceilings, sculptures

25. Ionic compounds: Found in minerals and rocks
Calcite = CaCO₃
Used in paint,
Antacids, calcium
Supplement for food

26. Ionic compound with polyatomic ions
Calcium sulfate in casts
Barium sulfate to absorb x-rays
Acetate uses
Sodium acetate
In Heat packs

28. Sodium hydrogen carbonate
(old name: sodium bicarbonate)
Medical: used in emergency situations to correct pH of blood
Baking soda: to make cakes rise

29. Bleach
Dentistry:
Clean and disinfect
Root canals
Rocket fuels:
Source of oxygen

30. POLYATOMIC IONS Examine the names & formulas:
What is the pattern? Do they end in “–ide?”
Ions with -1 charge
perbromate BrO4-1
bromate BrO3-1
bromite BrO2-1
hypobromite BrO-1
perchlorate ClO4-1
chlorate ClO3-1
chlorite ClO2-1
hypochlorite ClO-1
periodate IO4-1
iodate IO3-1
iodite IO2-1
hypoiodite IO-1
nitrate NO3-1
nitrite NO2-1
hydroxide OH-1
cyanide CN-1
thiocyanate SCN-1
acetate C2H3O2-1
Permanganate MnO4-1
bicarbonate HCO3-1
Ions with a -2 Charge
carbonate CO3-2
phthalate C8H4O4-2
sulfate SO4-2
sulfite SO3-2
chromate CrO4-2
dichromate Cr2O7-2
oxalate C2O4-2
peroxide O2-2
Ions with a -3 Charge
phosphate PO4-3
phosphite PO3-3
arsenate AsO4-3
Ions with +1 charge
ammonium ion NH4+1

31. Compounds vs. Polyatomic Ions

33. Polyatomic ions that you must know:
NAME
FORMULA
CHARGE
Nitrate
Acetate
Carbonate
Sulfate
Phosphate
Hydroxide
Ammonium

34. Using polyatomic ions:
Sodium + nitrate Calcium + nitrate
Formula
Name:

35. Writing Formulas (criss –cross method)
Cl¹⁻
CO₃²⁻ OH
SO₄²⁻
PO₄³⁻
NO₃¹⁻
Na¹⁺
NH₄¹⁺
Zn²⁺
Co³⁺

36. Ionic Compounds with Transition Metals
The transition metals are elements in Groups _____ to _______.
+ post transition metals: under the staircase.
Transition metals can have more than one charge.
Use Roman numerals after the name.
Roman numbers:
I = II = III = IV = V=

38. Transition metals Examples Iron II oxide Iron III oxide
Write the formulas for:
Copper I oxide
Cobalt III chloride
Nickel II sulfide

39. Formula Writing Practice
Sulfide
Sulfate
Oxide
Carbonate
Mercury II
Iron III
Iron II

40. Practice: Writing Binary Formulas
Many transition and post transition metals have multiple oxidation numbers (charges)
Ni: oxidation numbers of _____ & _____
Fe:
Find other examples:
Write formulas
Write names