NAMING COVALENT MOLECUL

ES9.2

NAMING MOLECULES Binary molecular compound

Covalently bonded compound containing only two different elements

Composed of 2 different nonmetals No ions or metals

NAMING BINARY MOLECULAR COMPOUNDS

1. Name the 1st element first using complete name.

2. Name the 2nd element using the root of the element and adding the suffix –ide

3. Prefixes are used to indicate the number of atoms that are present in the compound

1. Exception: first element in formula never uses mono-

4. Hydrogen bonded to 7A halogens (drop mono)

PREFIXES 1 - mon(o) 2 - di 3 - tri 4 - tetr(a) 5 - pent(a) 6 - hex(a) 7 - hept(a) 8 - oct(a) 9 - non(a) 10 - dec(a)

H - hyd C - carb N - nitr P - phosph As - arsen O - ox S - sulf Se - selen F - fluor Cl - chlor Br - brom I - iod

Nonmetal roots

PRACTICE PROBLEMS:

1. CO2. P2O5

3. CCl44. As2O3

5. NF3

6. SO2

1. Carbon monoxide2. Diphosphorus pentoxide3. Carbon tetrachloride4. Diarsenic trioxide5. Nitrogen trifluoride6. Sulfur dioxide

MORE PRACTICE…

1. H2O

2. NH3

3. N2H4

4. N2O

5. NO

Di hydrogen monoxideNitrogen trihydrideDinitrogen tetrahydrideDinitrogen monoxideNitrogen monoxide

1. Water2. Ammonia3. Hydrazine4. Nitrous oxide5. Nitric oxide

Common names

ACIDS Molecules can be put in aqueous

solution (water) and they make acids Compound classified as an ACID if it

releases H+ ions when put in water solution

Only name acids if molecule is put in water!!!

Two typesBinary AcidsOxyacids

BINARY ACIDS Hydrogen & one other element Sometimes there are more than 2

elements To name hydrogen, use prefix Hydro- Second element use Root (or form of root)

followed by suffix –ic If there are more than 2 elements involved, use

the root of the polyatomic ion that acid contains Add the word acid to the end Example: HCl

Hydrochloric acid Example: HCN

Hydrocyanic acid

OXYACIDS Acids that contain OXYANION What is an oxyanion?

Polyatomic ion that contains oxygen First: Determine anion present Use a form of the root of the anion Add suffix

Anion suffix –ate….oxyacid suffix= -icAnion suffix –ite….oxyacid suffix= -ous

Add the word acid Example:HNO3

Oxyanion: nitrate NO3-Oxyacid name: nitric acid

Example:HNO2Oxyanion: nitrite NO2-Oxyacid: nitrous acid

Hydrogen is not named in oxyacids!!!

NAMING ACIDS SUMMARY

Acids

Binary

Use HydroRoot – ic acid

Oxyacid

Use root of ion

ate ic acidite ous acid

Does NOT use hydro

PRACTICE…1. HI2. HClO3

3. H2SO4

4. H2S

5. HClO2

1. Hydroiodic acid2. Chloric acid3. Sulfuric acid4. Hydrosulfuric acid5. Chlorous acid

First determine if it’s a Binary acid or an oxyacid

NAME TO FORMULAS Write the symbols for the elements in

the order mentioned in the name. Write subscripts indicated by the

prefixes. If the first part of the name has no prefix, assume it is mono.

Prefixes tell you SUBSCRIPTS for each element

ExampleCarbon tetrachloride CCl4

WRITING FORMULAS FOR BINARY COVALENT COMPOUNDS: EXAMPLES

nitrogen dioxide NO2

diphosphorus pentoxide P2O5

xenon tetrafluoride XeF4

sulfur hexafluoride SF6

1 mono

2 di

3 tri

4 tetra

5 penta

6 hexa

7 hepta

8 octa

9 nona

10 deca

* Second element in ‘ide’ from

* Drop –a & -o before ‘oxide’

AIR POLLUTION CLASS WORK

Many common air pollutants form acids when dissolved in a water solution

Complete the following table

Formula of Pollutant

Name of Molecule

Formula of Acid

Name of Acid

SO2

Carbonic acid

NO2

HNO3