Nomenclature

Scientific Naming System

Nomenclature

What is the difference

between an element and a

compound?

DefinitionsElements cannot be broken down by

physical or chemical changes. Compounds are composed of 2 or more

elements that can be broken down by chemical change.

What type of matter can be broken down by physical changes?

IonsIons are elements with a charge. The reference table

lists these charges for each element. If the element is positive, it is called a cation.Cations are named the same as the element.

(Example: Ca=Calcium atom / Ca+2=Calcium ion)If the element in negative, it is called an anion.Anions are named ending with “-ide”

(Example: N=Nitrogen atom / N-3 = Nitride ion)

You try:Mg+2

K+

O-2

F-

Li+I-

Binary CompoundsBinary Compounds consist of only two of

elements. To name: write the complete name of the first element. The second element should then be named, ending in “-ide.”

NaCl sodium chlorideKI potassium iodideMgCl2Ca3N2

magnesium chloridecalcium nitride

You try…

Li3PAl2S3

SrBr2

Rb2OBaSeCsI

Criss-cross RuleTo write a formula, write the two ions

separately showing their charges. Charges are on the periodic table. Then, swap the two numbers and drop the sign:

Calcium nitride:Ca2+ N-3

Ca3N2

Lithium oxide: Li+ O-2

Li2O

Notice, we don’t write ones!

Problem:FeCl2 and FeCl3 are different

compounds but seem to have the same name. How can we name them different?

FeCl2 is iron (II) chloride FeCl3 is iron (III) chloride.

What do the roman numerals represent?

Transition Metals and nonmetals

Try these…FeCl2CuFZnON2O3

SO4

PCl3CH4

Careful: This rule doesn’t ALWAYS

work for cations. Find the anion’s charge and equalize that with the cation’s charge as a

check.

Try these…Potassium iodideMagnesium chlorideAluminum sulfideHydrogen oxideBarium selenideCesium phosphideStrontium phosphideCopper (II) flourideIron (III) telluride

Tertiary CompoundsWhen compounds have more than

2 elements, it contains a polyatomic ion.

Polyatomic ion are a group of 2 or more atoms that are bonded very strongly and act as one ion.

AgNO3 silver nitrate

Polyatomic ionsYou are given a list of polyatomic ions.

Naming compounds with these ions are easy once you familiarize yourself with the list.

CaCO3 calcium carbonateLiClO2 lithium chloriteNaOH sodium hydroxide(NH4)3PO4 ammonium phosphate

You try…K2SO4

CsNO2

Ba(SCN)2

SrClO3

Al(HCO3)3

RbCN

Try These…Name: Write the formula:Fe(SCN)2 Nickel (III) Nitride

CoCl3 Manganese (II) sulfite

NiBr2 Zinc sulfate

CuO Titanium (II) carbonate

MnI4 Gold (III) oxide

Ag2S Iron (III) Chloride

Game

http://www.sciencegeek.net/APchemistry/APtaters/directory.shtml

Covalent CompoundsIn some cases, binary covalent compounds

(compounds with nonmetals only) are named using prefixes and end in “-ide.” The prefixes used are listed below.

1 mono-2 di-3 tri-4 tetra-5 penta-6 hexa-7 hepta-8 oct-9 non-

Name or write the formula:NOH2O

PCl5Cl2O7

Carbon tetrachloridePhosphorous tribromideSilicon dioxide