1. Section 7.1 Chemical Names and Formulas
Note Taking Tips:
1. You do NOT need to write every word; get the high points so that what you recall later makes sense to you.
2. Abbreviate when u can!

2. Section 7.1 Naming Ions Atoms are electrically neutral.
Because there is the same number of protons (+) and electrons (-).
Ions are atoms, or groups of atoms, with a charge (positive or negative)
They have different numbers of protons and electrons.
Only electrons can move, and ions are made by gaining or losing electrons.

3. Section 7.1 Naming Ions
1. Monatomic ion – an ion formed from a single atom
11. Polyatomic ion – an ion made of two or more atoms acting as a single unit with a charge
*See Periodic Table of Ions (handout)

4. K1+ Ca2+ A Cation is… A positive ion. Formed by losing electrons.
Metals can lose electrons
Charge written as superscript on rt.
Has lost one electron (no name change for positive ions = potassium ion)
K1+
Ca2+
Has lost two electrons = calcium ion

5. A Cation Charge is…
When metals in Groups 1, 2 lose electrons, they form cations with positive charges equal to their group number

6. F1- O2- An Anion is… A negative ion. Has gained electrons.
Nonmetals can gain electrons.
F1-
Has gained one electron (-ide is new ending = fluoride)
O2-
Gained two electrons (oxide)

7. An Anion Charge is…
The charge of any ion of a nonmetal in group is determined by subtracting 18 from the group number.

8. Charge of Transition Metals…
The charge of cations of many transition metal ions must be determined from the number of electrons lost.

9. Ion High School

10. Predicting Ionic Charges
Group 1:
Lose 1 electron to form 1+ ions
H1+
Li1+
Na1+
K1+
Rb1+

11. Predicting Ionic Charges
Group 2:
Loses 2 electrons to form 2+ ions
Be2+
Mg2+
Ca2+
Sr2+
Ba2+

12. Predicting Ionic Charges
Group 13:
Loses 3
electrons to form
3+ ions
B3+
Al3+
Ga3+

13. Predicting Ionic Charges
Group 14:
Neither! Group 14 elements rarely form ions (except ones below metalloid line = Ge, Sn, Pb)
Do they lose 4 electrons or gain 4 electrons?

14. Predicting Ionic Charges
Nitride
Gains 3
electrons to form
3- ions
Group 15:
P3-
Phosphide
As3-
Arsenide

15. Predicting Ionic Charges
Oxide
Gains 2
electrons to form
2- ions
Group 16:
S2-
Sulfide
Se2-
Selenide

16. Predicting Ionic Charges
Gains 1 electron to form
1- ions
Group 17:
F1-
Fluoride
Br1-
Bromide
Cl1-
Chloride
I1-
Iodide

17. Predicting Ionic Charges
Group 18:
Stable noble gases do not form ions!

18. Predicting Ionic Charges
Transition elements:
Many have more than one possible oxidation state.
Note the use of Roman numerals to show charges
Iron (II) = Fe2+
Iron (III) = Fe3+

19. Naming cations
Two methods can clarify when more than one charge is possible:
12. Stock system – uses roman numerals in parenthesis to indicate the numerical value
13. Classical method – uses root word with suffixes (-ous, -ic)
Does not give true value

20. Naming cations
Classical method – uses root word with suffixes (-ous, -ic)
-ous = lower charge
- ic = higher charge
Does not give true value

21. Naming cations We will use the Stock system.
Cation - if the charge is always the same (like in the Group A metals) just write the name of the metal.
Transition metals can have more than one type of charge.
Indicate their charge as a roman numeral in parenthesis after the name of the metal (Table 9.2, p.255)

22. Predicting Ionic Charges
Some of the post-transition elements also
have more than one possible oxidation state.
Tin (II) = Sn2+
Lead (II) = Pb2+
Tin (IV) = Sn4+
Lead (IV) = Pb 4+

23. Predicting Ionic Charges
Some transition elements
have only one possible oxidation state, such as these three:
Transition Metals:
Silver = Ag1+
Zinc = Zn2+
Cadmium = Cd2+

24. Exceptions: Some of the transition metals have only one ionic charge:
Do not need to use roman numerals for these:
Silver is always 1+ (Ag1+)
Cadmium and Zinc are always 2+ (Cd2+ and Zn2+)

25. Practice by naming these cations:
Al3+
Fe3+
Pb2+
Li1+
sodium ion
calcium ion
aluminum ion
iron (III) ion
lead (II) ion
lithium ion

26. Write symbols for these:
Potassium ion
Magnesium ion
Copper (II) ion
Chromium (VI) ion
Barium ion
Mercury (II) ion
K1+
Mg2+
Cu2+
Cr6+
Ba2+
Hg2+

27. Naming Anions
Change the monatomic element ending to – ide
F1- a Fluorine atom will become a Fluoride ion.

28. Practice by naming these:
Cl1-
N3-
Br1-
O2-
chloride
nitride
bromide
oxide

29. Write symbols for these:
Sulfide ion
Iodide ion
Phosphide ion
S2-
I1-
P3-

30. Polyatomic ions are…
- groups of atoms that stay together and have an overall charge, and one name.
Most polyatomic anions end in –ate or -ite
Acetate: C2H3O21-
Nitrate: NO31-
Nitrite: NO21-
Permanganate: MnO41-
Exceptions:
Hydroxide: OH1- and Cyanide: CN1-?

31. Have your Periodic Table of Ions
Phosphate: PO43-
Phosphite: PO33-
Ammonium: NH41+
Sulfate: SO42-
Sulfite: SO32-
Carbonate: CO32-
Chromate: CrO42-
Dichromate: Cr2O72-
(One of the few positive polyatomic ions)
If the polyatomic ion begins with H, then combine the word hydrogen with the other polyatomic ion present: H CO → HCO hydrogen + carbonate → hydrogen carbonate ion

32. Important Information:
7.1 Practice Problems
Chapter 7 Vocabulary 1-10
Chapter 7 Notes: A-C
Activity: Naming Ionic Compounds due Wed
7.1 Reading Guide due Friday

33. Sec 7.1 Naming and Writing Formulas for Ionic Compound
2. Binary compound – composed of two elements and can be either ionic or molecular (covalent)
Ex: FeCl3 Al2S3

34. Chapter 7 Notes
To name any binary ionic compound, place the cation name first, followed by the anion name.

35. A. Writing Formulas for Ionic Compound
Example: Barium nitrate (note the 2 word name)
1. Write the formula for the cation followed by anion, including CHARGES
( )
Ba2+
NO3-
2. If the cation has ( ), the number in parenthesis is the charge. 2
Now balanced.
3. Use the criss-cross method to balance charges.
Not balanced!
= Ba(NO3)2
4. Use parentheses if you need more than one of a polyatomic ion.
5. reduce subscripts to lowest whole number ratio

36. Writing Ionic Compound Formulas
Example: Ammonium sulfate (note the 2 word name)
1. Write the formula for the cation followed by anion, including CHARGES
( )
NH4+
SO42-
2. If the cation has ( ), the number in parenthesis is the charge. 2
Now balanced.
3. Use the criss-cross method to balance charges.
Not balanced!
= (NH4)2SO4
4. Use parentheses if you need more than one of a polyatomic ion.
5. reduce subscripts to lowest whole number ratio

37. Writing Ionic Compound Formulas
Example: Iron (III) chloride (note the 2 word name)
1. Write the formula for the cation followed by anion, including CHARGES
Fe3+
Cl-
2. If the cation has ( ), the number in parenthesis is the charge. 3
Now balanced.
Not balanced!
3. Use the criss-cross method to balance charges.
= FeCl3
4. Use parentheses if you need more than one of a polyatomic ion.
5. reduce subscripts to lowest whole number ratio

38. Writing Ionic Compound Formulas
Example: Aluminum sulfide (note the 2 word name)
1. Write the formula for the cation followed by anion, including CHARGES
Al3+
S2-
2. If the cation has ( ), the number in parenthesis is the charge. 2 3
Now balanced.
3. Use the criss-cross method to balance charges.
Not balanced!
= Al2S3
4. Use parentheses if you need more than one of a polyatomic ion.
5. reduce subscripts to lowest whole number ratio

39. Writing Ionic Compound Formulas
Example: Zinc hydroxide (note the 2 word name)
1. Write the formula for the cation followed by anion, including CHARGES
( )
Zn2+
OH-
2. If the cation has ( ), the number in parenthesis is the charge. 2
Now balanced.
3. Use the criss-cross method to balance charges.
Not balanced!
= Zn(OH)2
4. Use parentheses if you need more than one of a polyatomic ion.
5. reduce subscripts to lowest whole number ratio

40. B. Naming Ionic Compounds
1. Name the cation first, then anion
2. Monatomic cation = name of the element
Ex. Ca2+ = calcium ion
3. transition and post-transition cations have ( ) if more than one charge (number in parenthesis is their charge).
4. Monatomic anion (off periodic table) = root + -ide
Ex. Cl- = chloride
CaCl2 = calcium chloride
5. Most polyatomic anions end in -ate or –ite (exception: cyanide and hydroxide)

41. Naming Ionic Compounds
(Metals with multiple oxidation states)
some metals can form more than one charge (usually the transition metals)
use a Roman numeral in their name:
PbCl2 – use the anion to find the charge on the cation (chloride is always 1-)
Pb2+ is the lead (II) cation
PbCl2 = lead (II) chloride

42. C. Things to remember about Ionic Cmpds
If cations have ( ), the number in parenthesis is their charge.
If anions end in -ide they are probably off the periodic table (Monoatomic)
If anion ends in -ate or –ite, then it is polyatomic

43. Practice Problems a) Ba2+, S2- b) Li+, O2- c) Ca2+, N3- d) Cu2+, I-
barium sulfide
Li2O
lithium oxide
Ca3N2
calcium nitride
CuI2
copper (II) iodide

44. Practice Problems a) sodium iodide b) stannous chloride
c) potassium sulfide
d) calcium iodide
Na+, I-
NaI
Sn2+, Cl-
SnCl2
K+, S2-
K2S
Ca2+, I-
CaI2

45. 7.1 Practice Problems p. 211: 1-2 p. 213: 1-2 p. 215: 1-2
Finish a set and turn to Appendix E page (R121) to check and correct your answers.. Self-correct.