1. Compounds
Molecular and Ionic

2. Molecular Compounds Molecular compounds
have relatively melting points and boiling points
do not conduct electricity when
may or may not conduct electricity when

3. Molecular Compounds Molecular compounds
exist as with definite composition
have individual molecules that are held together by relatively that are generally proportional to the size of the molecule
for the binary compound AB, the A is attracted than to other B’s

4. Molecular Compounds B A
Imagine that these are binary molecular compounds where the red end represents element A and the white end represents element B. A is attracted to all B’s but to one B more than the others

5. Molecular Compounds
Law of Definite Proportions: In a given compound, the elements are combined in a
This means that for something like water, H2O, there are always 2 H’s for every 1 O. There can never be water with 3 H’s for every 1 O or 2 H’s for every 3 O’s.

6. Molecular Compounds
Law of Multiple Proportions: When elements form more than one compound, the mass ratio of one element to the other in a compound is an of the ratio in another
Mass O : Mass C in carbon monoxide is 1.33:1
Mass O : Mass C in carbon dioxide is 2.67:1
This makes sense, since there is in CO2 as in CO

7. Binary Molecular Compounds
A binary molecular compound is composed of two
To name a binary molecular compound, it is necessary to use

8. Binary Molecular Compounds
Naming the first element:
Only use a prefix if there is atom of the first element
of the element’s name
Naming the second element:
use a prefix

9. Binary Molecular Compounds
The prefixes are:
1-mono
2-di
3-tri
5-penta
6-hexa
7-hepta
9-nona
10-deca

10. Binary Molecular Compounds
Name these compounds:
CCl4
P2O5
Give the formula for these compounds:
dinitrogen monoxide
oxygen difluoride

11. Ionic Compounds Ionic compounds have melting points and boiling points
conduct electric current when
conduct electric current when in

12. Ionic Compounds Ionic compounds
have a basic unit that is a of oppositely charged particles called
have empirical formulas giving the simplest integer ratio of the ions in a
NaCl is not a molecule but a series of Na+ ions surrounded by Cl- ions
Each Na+ ion is attracted equally by Cl- ions
Each Cl- ion is attracted equally by Na+ ions

13. Ionic Compounds
This is a crystal lattice of NaCl, a common ionic compound
Every Na+ ion (green) is surrounded by 6 Cl- (blue) ions

14. Ionic Compounds
This website will show how a NaCl unit cell repeats to form a crystal lattice.
Are there individual molecules in an ionic compound?

15. Ions
Ions are neutral atoms that have gained or lost electrons to develop a charge
Metals to form positive ions called
Nonmetals to form negative ions called

16. Ionic Charges
Representative elements have predictable charges

17. Ionic Charges
The transition metals may have multiple charges

18. Ionic Charges
Transition metals and those representative metals that are under the stair-step line may have possible charge
To differentiate between them, you must use a
Example: Cu1+ is copper (I) and Cu2+ is copper (II)

19. Binary Ionic Compounds
Binary ionic compounds consist of ions—a cation which is a metal and an anion which is a nonmetal.
Binary ionic compounds only contain
The ions’ charges must cancel in order to create a formula unit

20. Binary Ionic Compounds
Let’s say that you wanted to combine the metal Sr with the nonmetal I.
First, you would have to on Sr and the charge on I
Sr is in Group 2 and has a charge of
I is in Group 17 and has a charge of
Then, you would have to make sure the charges
It would take two I1-’s to cancel one Sr2+:

21. Naming Binary Ionic Compounds
Name the cation/metal first
NEVER use prefixees
the ending
If there are multiple charges, use a
Name the anion/nonmetal second
NEVER use prefixes
Change the ending to

22. Naming Binary Ionic Compounds
Name the following compounds:
LiF
MgCl2
Cu3N
Give the formulas for the following compounds:
calcium sulfide
iron (III) oxide

23. Naming Ternary Ionic Compounds
Name the cation first
Is it a polyatomic ion? If so, name it.
Is it a monatomic ion? If so, check to see if it needs a and then name it.
Remember, metal’s endings do not change!
Name the cation second
Is it a monatomic ion? If so, change the ending to .

24. Naming Ternary Ionic Compounds
Name the following compounds
Na2SO4
NH4CO3
Al(NO3)3
Give the formula of the following compounds
lead (II) acetate
calcium carbonate