Chemical Nomenclature

Naming compounds and writing chemical formulas.

Canton South Chemistry!

Predicting Charges on Monatomic Ions

+1 +2 +3 +4 +5 +2 +3

-4 -3 -2 -1 0

                                                   

Nomenclature refers to the process of naming chemicals.

Initially the focus is on the most basic rules and ideas involved in the naming of compounds.

Understanding Nomenclature

I. Binary Compounds A binary compound contains just two element

1. The element with the positive charge ( more metallic ), is written

first.

2. The element with the negative charge( more non-metallic) is written

second

Understanding Nomenclature

• The second word (negative ion) is formed by changing the ending

of the element name to “ide”.

For example: fluorine changes to fluoride, and oxygen to oxide

ex: NaCl sodium chloride

KBr potassium bromide

The first word (metal or positive ion) remains the same word

1. Using the rules given , name the compounds listed below. 

1. MgO ____________________ 2. CaI2__________________

 3. BaS ____________________ 4. ZnI2

______________________ 

5. CaO ____________________ 6. Ag2O_____________________

 7. K3P ____________________ 8.

AlBr3_____________________

 9. Na3N ____________________ 10.

MgS_____________________

Writing proper Chemical formulas.

potassium and chlorine =

1+

K Cl = KCl

1-

= 0

The net charge of the formula must be zero

potassium chloride

Crisscross Methodsimplified method for writing these formulas

Calcium and bromide = calcium bromide Ca2+ Br1-

= 0

Ca2+ Br1-

Ca2+ Br1-

1 2

2+ 2- = 0

1 2

**But we don’t write ones!!! CaBr2

Subscripts

Ca1Br2

Crisscross Methodsimplified method for writing these formulas

aluminum and sulfide = aluminum sulfide Al3+ S2-

= 0

Al3+ S2-

Al3+ S2-

2 3

6+ 6- = 0

2 3

Al2S3

Subscripts

Al2S3

12. sodium chloride ____________13. potassium iodide __________ 14. magnesium sulfide __________15. aluminum bromide__________ 16. strontium oxide ____________ 17. sodium sulfide __________ 18. rubidium phosphide _________19. barium nitride __________ 

Using the rule given , give the formula for these compounds

Groups/Families

• 23, 24, 23, 23, 23, 12, 2

• 1, 2

• 24, 13, 12

Fe Cu ZnNiCo Zn

Ag

Au HgHg

ZnMnCr

Pt

IA

IIA

I-VIIIB

VIAVIIA

VIIIA

+1 +2 -2 -1 0

multiple charges

-4

+3

-3

+2+4

+3+5

Cd

VA

+2+3

+2+4

+2+3

+1+3

+2+1

+2+3

+2+3

+1+2

+2+4

+1+2

+2

Some metallic element are capable of more than one positive charge. We will indicated these with a roman numeral in parenthesis following the name of

the positive element.

Type II Binary Compounds(Stock System)

Roman numeral = the + charge

iron (II) = 2+ and iron (III) = 3+

***Used only when:***

MORE THAN 1 POSITIVE CHARGE

iron and chloride =

Fe Cl 1-

Fe Cl1-

3

iron chloride

=

iron chloride

1 2

(II)

(III)

Compare FeCl2 & FeCl3

iron chloride

2-2+

3+ 3- 0

0

=

Type II Binary Compounds(Stock System)

***Used only when:***

MORE THAN

1 POSITIVE CHARGE

1

4. Name the following compounds. 

21. CuO ______________________ 22. PbS ________________________ 

23. HgCl ______________________ 24. MnO2 _________________________

 25. Fe2S3 ______________________ 26. SnBr2 ________________________

 27. BiCl3 ______________________ 28. PbCl4 ________________________

 

Type II Binary Compounds

lead (II) sulfide

Another method of indicating metallic ions with more than one charge is:

Classicalor

“Old School”The "ous"-"ic" System

a suffix

while the suffix -ic is used for the higher ionic charge

The suffix -ous is used for the lower charge.

*  Chemistry trivia time:

In the James Bond movie Goldfinger who was the villian?

Auric Goldfinger

What was the license plate number on Goldfinger's Rolls Royce?

   AU3 What was the name of Goldfinger's business establishment? 

Auric Enterprises

** Mercury's name was changed because hydroargentous and hydroargentic would be just to much to handle

29. ferric chloride ________________________ _____________ 

30. stannic oxide ________________________ _____________ 

31. mercuric iodide ________________________ _____________ 

32. cuprous oxide ________________________ _____________ 

33. plumbous sulfide ________________________ _____________ 

34. antimonic bromide _______________________ ____________ 

35. aurous phosphide ________________________ _____________

“Old School”

The "ous"-"ic" System

(“old school”) (Stock) formula

tin (IV) oxide SnO2

A ternary compound contains three or more different elements. 

Ternary compounds usually contain one or more polyatomic ions ( radicals ).

Polyatomic ions ( radicals )are treated just like an ion.

When writing the formula – the basic rules apply.

Ternary CompoundsIt takes “3” or more

Examples: Fe(ClO4)2 ; NaOH : NH4MnO4

Ex: Calcium hydroxide

Calcium and hydroxide = calcium hydroxide Ca2+ OH1-

= 0

Ca2+ OH1-

1 2

Ca OH 2

Subscripts

CaOH2

But OH2 = H2O = water !!!

***Parentheses : need to be used whenever more than a single polyatomic ion is needed to balance the charges

- in other words if you add a subscript put the polyatomic radical in parentheses.

( )

Determining Names and Formulas of Ionic Compounds

Containing Polyatomic Ions

Practice with Polyatomic Ions

NH4OH

Ba(OH)2

Fe(CN)3

Zn(C2H3O2)2

ammonium sulfide

plumbous hydroxide

ammonium hydroxide

barium hydroxide

iron (III) cyanide

zinc acetate

(NH4)2S

Pb(OH)2

... the `ate chart

CO32-CO3

2-

NO3-NO3

-

ClO3-ClO3

-CrO42-CrO4

2-

PO43-PO4

3-

MnO3-MnO3

-

SO42-SO4

2-

-3 -2 -1Polyatomic Ions – they all contain oxygen

... the `ate chart

ChemistryChemistry

NomenclatureNomenclature

ClassClassCrazyCrazy

PleasePlease

Manana ?Manana ?

StudyStudy

-3 -2 -1

... the `ate become… `ites– they all lose an oxygen..

but the charge remains the same

CO22-CO2

2-

NO2-NO2

-

ClO2-ClO2

-CrO32-CrO3

2-

PO33-PO3

3-

MnO2-MnO2

-

SO32-SO3

2-

-3 -2 -1

... the `ate; the `ite; now the hypo-– subtract another oxygen !!

and the charge remains the same

CO 2-CO 2-

NO -NO

-

ClO -ClO -CrO22-CrO2

2-

PO23-PO2

3-

MnO -MnO -

SO22-SO2

2-

-3 -2 -1

– lets add an oxygen … the Per- ... the `ate; the `ite; the hypo..

and the charge remains the same

CO42-CO4

2-

NO4-NO4

-

ClO4-ClO4

-CrO52-CrO5

2-

PO53-PO5

3-

MnO4-MnO4

-

SO52-SO5

2-

-3 -2 -1

ClO2-1

ClO4-1

ClO3-1

ClO-1

perchlorate

chlorate

chlorite

hypochlorite

`ate `ite hypo- per-

Na2CO3CO3-2

HCO3-1

carbonate

bicarbonate

carbonate versus bicarbonate

NaHCO3

sodium carbonate

sodium bicarbonate

add H+ and drop a negative charge

36. AlPO4 ______________________ 37. (NH4)2CO3 _______________________

 38. __________ lithium cyanide 39. ___________ copper(II) nitrate 40. KClO ______________________ 41. Zn(C2H3O2)2 ______________________

 42. __________ calcium phosphate 43. ___________ ammonium sulfite 44. __________ ammonium acetate 45. NaMnO4 _______________________

 

Determining Names and Formulas of Ionic Compounds Containing Polyatomic Ions

Naming Covalent Molecular Compounds

Use these Prefixes: Greek prefixes to indicate number (never use mono on first)

mono - 1 di - 2 tri - 3 tetra - 4 penta - 5 hexa - 6 hepta - 7 octa - 8nona - 9 deca – 10

Nonmetal to Nonmetal ( or to the right of the zigzag red line)

Ex: BF3 NO

N2O5

boron trifluoride

dinitrogen pentoxide

nitrogen monoxide

1. CO __________________________ 8. diphosphorus pentoxide _________________  2. PBr3 ______________________________ 9. carbon dioxide _________________

  3. CCl4 ______________________________ 10. selenium trioxide _________________

  4. NCl3 ______________________________ 11. sulfur hexafluoride _________________

  5. SeO2 ______________________________ 12. phosphorus pentiodide ________________

  6. P2O3 _____________________________ 13. sulfur tribromide ________________

  7. NH3 ______________________________ 14. phosphorus hexachloride______________

Naming Covalent Molecular Compounds