Chemical Nomenclature: A Tutorial*
Rules & Drills with Answers

* The format used here is designed for working online, with links to answers etc. and not suitable for converting into a hard copy.
If you prefer to work from a printed copy, click here to download a printable version of this tutorial (Adobe Acrobat Reader required). There is a total of 35 pages, including the answers to the drills.

For beginning students, the study of nomenclature (system of naming chemicals) can seem impossibly complex. For that reason, the rules and drills presented here are broken down into Units, and it is not advisable to study all the units at one sitting, but to take it one unit at a time. If you are not able to spread out your work over several days, you should at least take a break in between units.

OUTLINE:
Unit I: Chemical Symbols of Some Common Elements (Drill A)
Unit II: Nomenclature of Pure Elements (Drill B)
Unit III: Nomenclature of Monatomic Ions (Simple Ions)
Unit IIIA: Nomenclature of Monatomic Anions
Unit IIIB: Nomenclature of Monatomic Cations of Fixed Charges
Unit IIIC: Nomenclature of Monatomic Cations of Variable Charges (Drill C)
Unit IV: Nomenclature of Ionic Compounds of Monatomic Ions
Unit IVA: Writing Formulas from a Given Name (Drill D)
Unit IVB: Writing Names from a Given Formula (Drills E thru H)
Unit V: Nomenclature of Polyatomic Ions
Unit VA: The "Basic Eight" Polyatomic Ions (Drills I-1 thru I-4)
Unit VB: Polyatomic Ions with "- ite" Ending
Unit VC: Nomenclature of "- ate" and "- ite" Compounds (Drill I-5)
Unit VD: Nomenclature of Oxohaloanions (Drills J & K)
Unit VI: Nomenclature of Acids (Drill L)
Unit VII: Nomenclature of Acid Anions (Drill M)
Unit VIII: Nomenclature of Other Common Polyatomic Ions (Drill N)
Unit IX: Nomenclature of Molecular Binary Compounds (Drill O & P)
Unit X: Nomenclature of Hydrates (Drill Q)

Unit I: Chemical Symbols of Some Common Elements

You must first learn the symbols of some common elements. Your instructor may have different requirements on which elements you must learn. The ones listed below are the one you have to know to make use of this tutorial, and most likely they are the only ones you will ever have to know even as you move on to more advanced courses. You might want to put them on flash cards. You should drill yourself one way or another before you proceed to the next unit.

Notice that the elements below are boxed together in groups, some elements appearing in more than one group. My suggestion is you learn them in groups, in this order: Elements #1 through 18, Group IA, IIA, VIIA, VIIIA, Common Transition Elements, and finally, Other Common Elements. If you have trouble with spelling, you'll find it easier to learn correct spelling if you copy the names several times as you sound it out. If you think this is too much work, then you are taking the wrong course. Studying chemistry takes work, regardless of how smart you are.

Although you don't have memorize where these elements lie in the Periodic Table, but you would want to familiarize yourself with their locations so that you can find them quickly.  For that reason, you should always have the Periodic Table in front of you as you proceed through this Tutorial.  As a quick self-test, you should run through the list of elements on the Periodic Table (in groups as suggested) to see whether you can name them.

COMMON ELEMENTS: NAMES AND SYMBOLS

Learn the names (with correct spelling) and symbols of the elements listed below (no need to memorize numbers). Note that the symbols are capitalized. If the symbol consists of two letters, only the first letter is capitalized.

Elements # 1 - 18

1 H hydrogen							2 He helium
3 Li lithium	4 Be beryllium	5 B boron	6 C carbon	7 N nitrogen	8 O oxygen	9 F fluorine	10 Ne neon
11 Na sodium	12 Mg magnesium	13 Al aluminum	14 Si silicon	15 P phosphorus	16 S sulfur	17 Cl chlorine	18 Ar argon

Now test yourself by taking a simple Periodic Table that shows only the symbols and not the names (such as the one I hand out in class), and write down the names of the elements from #1 through 18.

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Learn the elements in Groups:  Group IA, Group IIA, Group VIIA, Group VIIIA.
You may have noticed that you had already learned some of the elements as part of the group listed above.  They are repeated here so that you would associate these elements as part of the Groups specified (IA, IIA... etc.)

Group IA	Group IIA	Group VIIA	Group VIIIA
H hydrogen		(H) (hyrogen)	He helium
Li lithium	Be beryllium	F fluorine	Ne neon
Na sodium	Mg magnesium	Cl chlorine	Ar argon
K potassium	Ca calcium	Br bromine	Kr krypton
Rb rubidium	Sr strontium	I iodine	Xe xenon
Cs cesium	Ba barium		Rn radon
Fr francium	Ra radium

Again, test yourself by looking at a simple Periodic Table, and name the elements group by group.

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Learn the elements in the first row of the group referred to as "Transition Metals"

Sc scandium

Ti titanium

V vanadium

Cr chromium

Mn manganese

Fe iron

Co cobalt

Ni nickel

Cu copper

Zn zinc

Test yourself before going on.

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 Learn 6 more Transition Metals.  Locate them on your Periodic Table.

Pd palladium	Ag silver	Cd cadmium
Pt platinum	Au gold	Hg mercury

Test yourself before going on.

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To complete the list, learn the "Other Common Elements" shown below.  Locate them in your Periodic Table.

Other Common Elements
	As arsenic	Se selenium
Sn tin	Sb antimony	Te tellurium
Pb lead	Bi bismuth
U uranium	Pu plutonium

Test yourself before going on.

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Drill A: Nomenclature of Elements

This is a self-test, since you can easily look up answers yourself. Take this as a practice test, after you have drilled yourself on the symbols and spelling of the elements listed above.

Name	Symbol	Symbol	Name
chlorine		S
calcium		K
arsenic		Fe
mercury		Na
copper		P

Remember not to proceed to the next unit until you have studied Unit I.
To check your answers, note you are at Drill A and

Click here to see answers.
Click here to return to OUTLINE

Unit II: Nomenclature of Pure Elements

The term, "Pure Elements", refers to elements when they are not combined with other elements such as in compounds. Certain pure elements exist in clusters, joined by covalent bonds, called molecules. For example, pure nitrogen exists as N₂ rather than N. When nitrogen is not part of a compound, it is also referred to as "free nitrogen" or "nitrogen in its elemental state".

Formulas of Pure Elements

Note that they are shown below according to their locations in the Periodic Table.

DIATOMIC MOLECULES:			H2
	N2	O2	F2
			Cl2
			Br2
			I2

OTHER MOLECULAR ELEMENTS:

P4

S8

Monatomic elements: with a few exceptions, all others are monatomic (e.g. He, Ne, Fe, Al are monatomic).

Exceptions:

· Elemental oxygen also exists in a less stable form as O₃ (ozone).

· Although we usually write C for pure carbon, it usually exists as an extended network of various types. Refer to your textbook if you are interested in these various "allotropes " of carbon.  by convention we will simply write C as if it were monatomic.

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Physical States of Pure Elements

Again note these are listed below according their locations in the Periodic Table.

GASES:			H2	He
	N2	O2	F2	Ne
			Cl2	Ar
				Kr
				Xe
				Rn

LIQUIDS: Br₂ and Hg

SOLIDS: with a few exceptions, all others are solids (e.g. K, Fe, Co, Sn, U are solids.)

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Drill B: Formulas and Physical States of Pure Elements

To make the best use of the drills in this tutorial, you should first study and memorize the above rules on the formulas and physical states of pure elements. Then write down the answers to the drill (rather than keeping them in your head). Answers are provided in a later part of this exercise, but do not check your answers until you have written down your answers to the entire drill. This takes discipline, but it would do you no good to flip to the answers without having put thought and time in working out the answers first.

Using only a periodic table, give the formulas and physical states of the elements specified. Specify the physical states with (g), (l) or (s).   [Example: fluorine = F₂ (g)]

chlorine	bromine	sulfur
argon	phosphorus	lead
nitrogen	krypton	element #112
chromium	mercury	gold
strontium	iodine	hydrogen

To check your answers, note that you are at Drill B then
Click here to see answers.
Click here to return to OUTLINE.

Unit III: Nomenclature of Monatomic Ions (Simple Ions)

"Simple Ions" refer to ions that are charged atoms, as opposed to charged molecules. They are therefore also known as monatomic ions.

Unit IIIA: Nomenclature of Monatomic Anions

A negatively charged ion is known as an "anion". Its name ends with -ide. For example, the chlorine ion is named chloride, and the phosphorus ion is named phosphide. The charge of a monatomic anion can be determined by its Group number in the periodic table. An anion in Group VIIA has a charge of 1- . An anion in Group VIA has a charge of 2- , etc. See Table below.

NAMES OF MONATOMIC ANIONS (SIMPLE ANIONS)
IVA	VA	VIA	VIIA
			H^- hydride
C^4^- carbide	N^3^- nitride	O^2^- oxide	F^- fluoride
	P^3^- phosphide	S^2^- sulfide	Cl^- chloride
	As^3^- arsenide	Se^2^- selenide	Br^- bromide
		Te^2^- telluride	I^- iodide

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Unit IIIB: Nomenclature of Monatomic Cations of Fixed Charges

A positively charged ion is known as a cation. Cations in Group IA, IIA and aluminum have fixed charges (i.e. nonvariable charges). Those in Group IA always have a charge of 1+, and those in Group IIA, a charge of 2+. The aluminum ion always has a charge of 3+. The name of a monatomic cation of fixed charge is merely the name of the element followed by the word "ion". Thus Na⁺ is "sodium ion". It is not necessary to specify the charge since it is nonvariable. There are a few other cations that also fall in this category, but we will keep it simple for now and stick with just Groups IA, IIA and aluminum.

NAMES OF MONATOMIC CATIONS (SIMPLE CATIONS)
IA	IIA	IIIA
H^+hydrogen ion
Li^+ lithium ion	Be^2+ beryllium ion
Na^+ sodium ion	Mg^2+magnesium ion	Al^3+ aluminum ion
K^+ potassium ion	Ca^2+ calcium ion
Rb^+ rubidium ion	Sr^2+ strontium ion
Cs^+ cesium ion	Ba^2+ barium ion
Fr^+ francium ion	Ra^2+ radium ion

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Unit IIIC: Nomenclature of Monatomic Cations of Variable Charges

Cations not named above are assumed to be of variable charges. For example iron can exist with various charges, the most common of which are in the form of Fe²⁺ and Fe³⁺. Their names must therefore specify the charges. This is done by following the name of the element with the charge in Roman numerals, within parentheses. Fe²⁺ is named iron(II) ion, and Fe³⁺ is named iron(III) ion. Tin(IV) ion refers to Sn⁴+. Names based on this system of nomenclature are known as "Stock names".

Many of these ions have "common names". Of the two most common ions, the one with the lower charge has the ending -ous, and that with the higher charge has the ending - ic. Thus Fe²⁺ has the common name, of ferrous ion. Fe³⁺ has the common name of ferric ion. Since some of these names are indeed quite commonly used (as in food labels), it would be wise to learn at least the four common names included in the table below.

Formula	Stock Name	Common Name
Fe^2+	iron(II) ion	ferrous ion
Fe^3+	iron(III) ion	ferric ion
Cu^+	copper(I) ion	cuprous ion
Cu^2+	copper(II) ion	cupric ion

Since the ending (-ous or –ic) in the common name specifies the charge, it would be redundant (therefore wrong) to also include the Roman numeral. Thus Cu⁺ should not be named as cuprous(I) ion. Incidentally, the ending –ous does not indicate the charge is 1+, nor 2+. The –ous ending indicates the lower charge of the two most common charges. In the case of iron, the two common charges are 2+ and 3+, so the lower charge would be 2+. Thus ferrous refer to Fe²⁺ rather than Fe³⁺.

Note: Your instructor may not require you to learn the common names.

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Drill C: Nomenclature of Monatomic Ions

Again, study the rules before taking this as a practice test. Write down your answers and compare them with the answers provided only after you have finished the entire drill.You may use only a periodic table.

FORMULA	NAME	NAME	FORMULA
Rb^+		nitride
Ba^2+		iodide
P^3-		oxide
Br^-		chromium(III) ion
N^3-		potassium ion
S^2-		aluminum ion
V^3+		magnesium
Cu^2+		iron(II) ion
Ca		copper(I) ion

To check your answers, note that you are at Drill C then
Click here to see answers.
Click here to return to OUTLINE.

Unit IV: Nomenclature of Ionic Compounds of Monatomic Ions

An ionic compound is generally made of one type of cation combined with one type of anion. The formula has no net charge even though the ions themselves are charged. Thus, the number of cations and the number of anions present must reflect a net charge of zero. These numbers appear as subscripts, immediately following each element.

For example, Na⁺ combines with Cl^- to form NaCl (net charge of zero, so no charges are shown). When Na⁺ combines with O^2- , however, you will need two Na⁺ to neutralize the charge of 2- on the oxygen, to give Na₂O. When Mg²⁺ combines with Cl^- , you will similarly need two Cl^- to neutralize the charge of 2+ on the magnesium, to give MgCl₂. Note that the subscript 2 refers only to the number of Cl, and not the number of Mg. When no subscript shows, it is assumed to be one. Thus, the formula MgCl₂ tells us that there is one Mg ion for every two Cl ions. The subscripts show us the simplest ratio of cation to anion. (It would be wrong to write Mg₂Cl₄ because 2:4 can be reduced to 1:2.)

When you combine Al³⁺ with O^2-, in order to come up with a net charge of zero, you would need two Al³⁺ and three O^2- , to give Al₂O₃. You can arrive at this answer by simply thinking about how the charges must work out, or use the Cross Over Method.

The Cross Over Method is merely a fast way to figure out how to make the net charge come out zero. It does not mean that Al now becomes 2- and oxygen now becomes 3+. Note also that in the Cross Over Method, the signs (charges) do not cross over (i.e. charges do not appear in the subscript.) Remember that in this method, you must always check that the subscripts are always reduced to the simplest ratio.

Even though there are ions (and charges) present in the compound, we do not show the charges in these formulas. It would be improper to write Al³⁺₂O^2-₃ or Mg²⁺O^2- , unless you needed to stress the charges for a special reason.

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Unit IVA: Writing Formulas from a Given Name

First figure out the charges of the cation and the anion by examining the name. Then combine the ions in a ratio that gives you a net charge of zero as described above. If you have trouble deciding what the charges are on the ions, you need to review Unit III ! You should be able to do the drill without using anything but a periodic table.

For example, given the name, tin(II) oxide, you know that the ions are Sn²⁺ and O^2-. (If you don’t know how I came up with these ions, you need to review Nomenclature Unit III.)
To write the formula for the compound with Sn²⁺ and O^2-, you examine the charges and can see that it will take one Sn²⁺ and one O^2- to form a neutral compound.

Let’s look at another example. Given the name, tin(IV) oxide, you know that the ions are Sn⁴⁺ and O^2-. In order to form a neutral compound, we must have one Sn⁴⁺ and two O^2-. The formula must therefore be SnO₂.

Now try out the Drill D.

Drill D: Formulas of Ionic Compounds of Monatomic ions

NAME	FORMULA
magnesium fluoride
lithium sulfide
calcium selenide
nickel(II) fluoride
copper(II) bromide
chromium(III) sulfide
tin(II) phosphide

To check your answers, note that you are at Drill D then
Click here to see answers.
Click here to return to OUTLINE.

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Unit IVB: Writing Names from a Given Formula

Examine the formula. If the cation belongs in the group that has fixed charges, then you just name the cation, followed by the name of the anion, but drop the word "ion" that comes in between. For example NaCl is sodium chloride, and not sodium ion chloride. MgCl₂ is magnesium chloride.

Drill E: Writing Names of Compounds with Cations of Fixed Charges

KBr

Li₂O

Mg₃As₂

Na₃P

To check your answers, note note that you are at Drill E then
Click here to see answers.

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If the cation belongs in the group that has variable charges, you must figure out what that charge is from the charge of the anion (which is always fixed). Do not use the Cross Over Method as it may lead to the wrong answer. For example, the formula SnO tells us that Sn must have a charge of 2+ since the oxygen ion is always 2- . If you used the Cross Over Method, you would have erroneously come up with Sn having 1+ charge. The Cross Over Method may seem to work, but it works only in some and not all cases. So, it would be wiser not to use it at all for going backwards (from formula to name).

Remember that the charge is per ion. Thus, Cu₂S tells us that Cu had a charge of 1+, not 2+. Since the S ion is always 2- (Group VIA), the two Cu must have a total charge of 2+. Thus each Cu must have 1+.

Drill F: Determining the Charge and Name of the Cation First, Then Name of Compound

Formula	Charge of Cation	Name of Cation	Name of Compound
MnO2
PbS
Cr2O3
Rb2Se
CuCl2
CuO
Cu2O

Check your answers to the above drill before going on. If you have made any mistakes be sure you find out why before you continue to the next drill. If necessary you should review all the previous Units.

To check your answers, note that you are at Drill F then
Click here to see answers.

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Drill G: Nomenclature of Ionic Compounds of Monatomic Ions (Both Fixed & Variable Charges)

FORMULA	NAME	FORMULA	NAME
	sodium oxide	RbBr
	magnesium nitride	FeBr2
	copper(I) sulfide	PbS
	manganese(II) iodide	Ba0
	iron(III) phosphide	K20
	copper(II) oxide	SbBr3
	tin(II) nitride	Fe3P2
	strontium oxide	Li2Se
	tin(IV) oxide	CuCl2

Check your answers to the above drill before going on. If you have made any mistakes be sure you find out why before you continue to the next drill. If necessary you should review all the previous Units.

To check your answers, note that you are at Drill G then
Click here to see answers.

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Extra Drill H: Nomenclature of Ionic Compounds of Monatomic Ions (Both Fixed & Variable Charges)

FORMULA	NAME
RaCl2
BiCl3
Fe203
CdBr2
Mn0
Mn02

To check your answers, note that you are at Drill H then
Click here to see answers.
Click here to return to OUTLINE.

Unit V: Nomenclature of Polyatomic Ions

Unit VA: The "Basic Eight" Polyatomic Ions

In this unit you are asked to memorize the names and formulas of 8 polyatomic ions, to start with. You will be asked to learn more later on. "Learning" means memorizing the correct spelling of the name, the correct subscript(s) and charge of each ion.

1+	1-	2-	3-
NH4^+ ammonium	C2H3O2^- acetate*	CO3^2^- carbonate	PO4^3^- phosphate
	NO3^- nitrate	SO4^2^- sulfate
	OH^- hydroxide
	ClO3^- chlorate

*acetate is also written as CH₃CO₂^-

In memorization, it helps to look for patterns. Note that all but two of the ions have the ending "- ate". For the ions with a charge of 1- , look up where the first element of each ion is located on the period table (C, N, O, Cl). Study the formulas and names of this group of ions before moving on to ions with a charge of 2- . Again look up the location of the first element of each ion in the periodic table (C and S). Study these two names and formulas, and finally move to the ion with a charge of 3- . Look up the position of P in the periodic table. After you have studied each group based on charges, put them on flash cards and test yourself over and over.

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Drill I - 1: Nomenclature of the "Basic Eight" Polyatomic Ions

NAME	FORMULA	FORMULA	NAME
sulfate		OH^-
acetate		SO4^2^-
chlorate		NH4^+
ammonium		NO3^-