1. Unlocking the secret identity of chemical compounds
Naming Chemicals
Unlocking the secret identity of chemical compounds

2. Monatomic Ions Monatomic ions Ions formed from a single atom
The Alkali metals lose one electron making 1+ ions
The Alkali earth metals lose two electrons making 2+ ions
The nitrogen family gains 3 electrons making 3- ions
The oxygen family gains 2 electrons making 2- ions
The Halogens gain 1 electron making 1- ions

3. Group 14 (carbon Family)
These elements tend to not lose all the electrons but share electrons leading to different ions
Sn (tin) will lose two electron from the outer P block and keep the two from the outer S block
Therefore making 2+ cations

4. The d-block (transition elements)
Can form 2+, 3+ and in a few cases 1+ or 4+ ions
Many form two ions of different charges
Ex. Copper forms 1+ and 2+ cations
Iron and chromium 2+ and 3+
Vanadium 2+, 3+, and 4+ cations

5. Naming monatomic ions
Monatomic cations are identified simply by the element's name.
K+= Potassium cation
Mg2+= Magnesium cation
Monatomic anions slightly more difficult
The ending to the element name is dropped and ide is added

6. Binary ionic compounds
Compounds composed of two different elements
Charges must cancel each other out so that it equals zero
Ex. Al3+ O2-
3+ so need 3-
Only 2- so 2 times 3+ =6+ and 3*2-= 6-
Al2O3

7. Naming binary Ionic compounds
The name of the cation is given first followed by the anion
No ratios need to be given
Expected to know or figure out these ratios if needed

8. The stock system of Nomenclature
Some elements have more than one cations
Need to distinguish these
Do this with roman numerals
Ex CuCl2
Copper(II)chloride

9. Binary molecular compounds
Rule #1
The less-electronegative element is given first.
Remember right to left up to down
It only gets a prefix if it contributes more than one
Rule #2
a) give a prefix indicating number
B) the root of the name of the second element
C) the ending -ide

10. Continued
Rule #3
The o or a at the end of a prefix is usually dropped when the word following the prefix is a vowel
Ex monoxide
pentoxide

11. Covalent-Network Compounds
Atoms is joined to neighbors by covalent bond
Subscripts in formula indicate smallest whole-number ratio
Similar to naming molecular compounds
Ex. SiC= silicon carbide
SiO2 = silicon dioxide
Si3O2 = silicon dioxide
Si3N4 = Trisilicon tetranitride

12. Acid An acid is a distinct type of molecular compound
More on acids later
Acid usually refers to a solution in water of one of the special compounds rather than to the compound itself
Ex. Hydrochloric acid refers to a water solution of HCl.

13. Common Binary Acids HF=hydrofluoric acid HCl= hydrochloric acid
HBr=hydrobromic acid
HI=hydriodic acid
H3PO4=phosphoric acid
HNO2=nitrous acid
HNO3=Nitric acid
H2SO3=Sulfurous acid
H2SO4=Sulfuric acid

14. Contin… CH3COOH= acetic acid HClO= hypochlorous acid
HClO2= chlorus acid
HClO3= chloric acid
HClO4= perchloric acid
H2CO3= carbonic acid

15. Salts
An ionic compound composed of a cation and the anion from an acid
Some contain anions in which one or more hydrogen atoms from the acid are retained
Named by adding the word hydrogen or the prefix bi- to the anion name
H2CO3 = 𝐻𝐶𝑂 − 3
Hydrogen cabonate ion
Bicarbonate ion

16. Oxidation Numbers
As a general rule oxidation numbers, shared electron are assumed to belong to the more-electronegative atom in each bond

17. Oxidation rules
1. the atoms in a pure element have an oxidation number of zero. Ex. Oxygen 02
2. the more-electronegative element in a binary molecular compound is assigned the number equal to the negative charge it would have as an ion. The less-electronegative same number as cation

18. Oxidation rules
3. Fluorine has an oxidation number of -1 in all of its compounds because it’s the most electronegative element
4. Oxygen has an oxidation number of -2 in almost all compounds.
Exceptions
Peroxides=-1 ex H2O2
Compounds with halogens = +2 ex OF2

19. Oxidation rules
5. Hydrogen has an oxidation number of +1 in compounds with element that are more electronegative
-1 with metals
6. The algebraic sum of oxidation numbers of all atoms in neutral compound is zero
7. The algebraic sum in polyatomic ion is equal to charge of ion

20. Oxidation rules
8. Rules 1-7 apply to covalently bonded atoms but oxidation numbers can be assigned to ionic compounds
The oxidation number of a monatomic ion is equal to the charge of said atom
Ex. Na+ = +1
Ca += +2
Cl- = -1

21. Formula mass
Formula mass of any molecule, formula unit or ion is the sum of the average atomic masses of all the atoms represented in its formula.
Ex 𝐻 2 O
H= 1.01 X 2= 2.02
O= 16.00
Average mass of water molecule= 18.02

22. Let’s do some
𝐻 2 𝑆𝑂 4
Ca( 𝑁𝑂 3 ) 2
Mg 𝐶𝑙 2

23. Molar Masses
Remember that molar mass is equal to the atomic mass number.
And one mole is equal to X particals
So lets consider 𝐻 2 O again
Each mole of water contains
2 moles of H
1 mole of O
So H=1.01 X 2= 2.02
O=16.00
Add them together and the molar mass for water is 18.02

24. Conversion Factors Simple flow chart For molecules Elements
Mass Moles Number of molecules
Elements
Mass Moles Number of particles

25. Lets do some What is the mass in grams of 2.50 mol of oxygen gas?
How many moles of compound are there in the following?
6.60 g (𝑁𝐻 4 ) 2 𝑆𝑂 4
4.5 kg 𝐶𝑎(𝑂𝐻) 2

26. Percent Composition
This can be very useful in determining how a molecule will form.
The formula for this is
𝑚𝑎𝑠𝑠 𝑜𝑓 𝑒𝑙𝑒𝑚𝑒𝑛𝑡 𝑖𝑛 𝑠𝑎𝑚𝑝𝑙𝑒 𝑜𝑓 𝑐𝑜𝑚𝑝𝑜𝑢𝑛𝑑 𝑚𝑎𝑠𝑠 𝑜𝑓 𝑠𝑎𝑚𝑝𝑙𝑒 𝑜𝑓 𝑐𝑜𝑚𝑝𝑜𝑢𝑛𝑑 X100
Lets do one
Find the percentage composition of Copper(I) sulfide, Cu2S

27. Determining chemical formulas
First step is to assume that you have a g sample of the compound.
Next using the percent composition figure out the masses of all the different elements
Next using the masses of the different elements figure out the number of moles in each by using their molar masses
Finally use the moles found to determine the molar ratio in the smallest whole numbers.

28. Lets do some
Quantitative analysis shows that a compounds contains 32.38% sodium, 22.65% sulfur, and 44.99% oxygen. Find the empirical formula of this compound.

29. Calculation of molecular formulas
Empirical formula is the lowest possible whole number ratio
The molecular formula is how it appears in its natural state.
X(Empirical formula)=Molecular formula