Naming Compounds
Sections (Zumdahl 6th Edition) 2.8-2.9
Outline: The Foundation of Stoichiometry
The Periodic Table helps organize types
Binary Compounds: Metal and Non-Metal
Binary Compounds: Two Non-Metals
Acids (with and without oxygen)
Problems: 2.30-2.35,
Naming Exercises 2.36-38, Ions 2.39, 2.42
Discussion Questions (2:1-2.17)
You will always have a periodic table available to you when
doing problems or taking exams, so start using it now.
The Periodic Table
• A two dimensional classification scheme for the
elements. The columns or groups arrange the elements
by chemical classification, as discussed above. The
chemical variation across the rows or periods reflect the
cyclic variation exhibited in the graphs above.
• The periodic table is not only an organizing principle,
but it has predictive power as well.
• As valuable as the periodic table is, the explanation of
its organization was not obvious. It was not until the
advent of quantum mechanics that the electronic
structure of the atoms could be used to explain the
periodic variation in properties.
Classification of the Elements
• Most of the elements are metals - metallic
luster, ability to conduct electricity and heat,
and malleability.
• The remaining elements are classified as
nonmetals - no luster, poor conductors of
electricity and heat and brittleness.
• There are only 11 non-metals and they are
grouped together in the periodic table
• Elements in periodic table are laid out by
increasing atomic number going across,
then down
← 2 ⋅1 →
Periodic Table
H
Li Be
NaMg ←
K Ca Sc Ti
Rb Sr Y Zr
Cs Ba La Hf
Fr Ra Ac Rf
←
⋅ 3 He
→
2
B C N
2
⋅ 5
→ Al Si P
V Cr Mn Fe Co Ni Cu Zn Ga Ge As
NbMo Tc Ru Rh Pd Ag Cd In Sn Sb
Ta W Re Os Ir Pt Au Hg Tl Pb Bi
Du Sg Bo HaMe
O
S
Se
Te
Po
F Ne
Cl Ar
Br Kr
I Xe
At Rn
Ce Pr Nd PmSm Eu Gd Tb Dy Ho Er TmYb Lu
Th Pa U Np PuAmCmBk Cf Es FmMd No Lr
←
2
⋅
7
→
The Alkali Metals
The Halogens
The Alkaline
Earth Metals
The Noble Gases
Groups in the Periodic Table
Main Group Elements (Vertical Groups)
Group IA - Alkali Metals
Group IIA - Alkaline Earth Metals
Group IIIA - Boron Family
Group IVA - Carbon Family
Group VA - Nitrogen Family
Group VIA - Oxygen Family (Calcogens)
Group VIIA - Halogens
Group VIIIA - Noble Gases
Other Groups ( Vertical and Horizontal Groups)
Group IB - 8B - Transition Metals
Period 6 Group - Lanthanides (Rare Earth Elements)
Period 7 Group - Actinides
Non-Metals
• Chalcogens - (oxygen, sulfur, selenium and
tellurium) - form 1:1 compounds with
alkaline-earths, but 2:1 compounds with
alkali-metals.
• Halogens - (fluorine, chlorine, bromine and
iodine) - highly reactive and form 1:1
compounds with alkali-metals.
• Noble gases - (helium, neon, argon, krypton,
radon) - virtually inert to chemical reactions.
• Nitrogen (Phosphorous), Carbon and Boron.
Naming Ions
Transition Metal Ions
Naming Binary Compounds (Type I; Ionic)
• Binary – only two elements (as ions) combined
• Can’t combine two metals (e.g. Cu & Zn –Brass)
• The metal ion (cation, or positive) is always
named first and the anion second.
• A monatomic cation takes its name from the name
of the element, e.g. Na+ is called sodium in the
names of compounds containing this ion.
• The non-metal ion , anion,(or negative ion) is
named by taking the first part of the element and
adding –ide, e.g. Cl- is chloride.
The Periodic Table of the Elements
H
Li Be
Na Mg ←
K Ca Sc Ti
Rb Sr Y Zr
Cs Ba La Hf
Fr Ra Ac Rf
He
F Ne
Cl Ar
Br Kr
I Xe
At Rn
B C N O
2
⋅ 5
→ Al Si P S
V CrMn Fe Co Ni Cu Zn Ga Ge As Se
NbMo Tc Ru Rh PdAg Cd In Sn Sb Te
Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po
Du Sg Bo Ha Me
The Transition Metals
Ce Pr Nd PmSm Eu Gd Tb DyHo Er TmYb Lu
Th Pa U Np PuAmCmBk Cf Es FmMd No Lr
Lanthanides: The
Rare Earth Elements
The Actinides
How do we know what charge to make each ion?
• The periodic table is our best source of
information (a great “cheat sheet”)
• Metals in column 1 give up one electron,
etc.
• Non-metals in column 7 take one electron.
• Notice the ions have the number of
electrons that the nearest inert gas has.
– Å This is the key
• Once the charge on each atom is chosen the
molecular formula can be determined.
Problem: Give the Name and Chemical Formulas of the
Compounds formed from the following pairs of Elements
(Notice: Some are not simple one-to-one, although they are
binary)
a) sodium and oxygen
Na2O
sodium oxide
CaF2
calcium fluoride
b) zinc and chlorine
c) calcium and fluorine
d) strontium and nitrogen
e) hydrogen and iodine
f) scandium and sulfur
HI
hydrogen iodide
(Type II; Ionic) Binary Compounds
• Applies to cations that can take on alternate charge
states
• Non-metals do not take on multiple charges when
combining with metals.
• When given the molecular formula of the Binary
Compound Æ Use the principle of charge balance
to determine the cation charge.
• Include in the cation name a Roman numeral
indicating the charge.
• An alternative to the Roman numeral is the name
change by adding ‘ic’ or ‘ous’ – stannous fluoride,
ferric chloride.
Small Molecules
F, S, O, N, I, Cl, P Containing Molecules
Polyatomic ions
The Periodic Table of the Elements
H
Li Be
NaMg
K Ca Sc Ti
Rb Sr Y Zr
Cs Ba La Hf
Fr Ra Ac Rf
B C N
Al Si P
V CrMn Fe Co Ni Cu Zn Ga Ge As
Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb
Ta W Re Os Ir Pt Au Hg Tl Pb Bi
Du Sg Bo Ha Me
O
S
Se
Te
Po
F
Cl
Br
I
At
Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
Th Pa U Np PuAmCm Bk Cf Es FmMd No Lr
Boron family
Nitrogen family
Carbon Family
Oxygen Family
He
Ne
Ar
Kr
Xe
Rn
Type I
Naming Type II Metals
Determining Names and Formulas of Ionic Compounds
of Elements That Form More Than One Ion.
Problem: Give the systematic names for the formulas or the
formulas for the names of the following compounds.
a) iron (III) sulfide - Fe is 3+, and S is 2- therefore the compound is:
Fe2S3
b) CoF2 -
c) stannic oxide - Stannic is the common name for tin (IV), Sn4+, the
oxide ion is O2-, therefore the formula of the compound is:
SnO2
d) NiCl3 -
Binary Compounds (Type III);
Covalent – contain Two Nonmetals
• Two Non-metals can make a molecule (unlike two metals)
• How many possible non-metal binary molecules are there?
• Covalent is the name given to the type of bond holding
them together; distinct from ionic.
• The first element in the formula is named using the full
element name.
• The second element is named as if it were an anion. (just as
with ionic compounds).
• Prefixes are used to denote the numbers of atoms present.
• The prefix mono- is never used for naming the first
element, e.g. CO is carbon monoxide.
• Which element comes first? (The more metal-like one)
Naming Covalent Molecules
Examples SO2, sulfur
dioxide.
CO carbon monoxide
CO2 carbon dioxide
ClF3 chlorine
trifluoride
Summary of Binary Compounds
• Combine Metal with Metal
– Not interesting; just alloys; so 90% of all combinations
do not result in a new molecule
• Combine Metal with NonMetal
– Metal donates; NonMetal accepts electrons
– Halides give salts; other nonmetals give brittle
compounds.
• Combine NonMetal and NonMetal
– Both NonMetals must share electrons (unevenly)
Polyatomic Ions
• Need to develop common acids (and bases) from
the binary compounds
• From there make polyatomic salts from the acids.
• Simple acids are HX, where X is a halogen.
Looks like a salt but H is a bit unusual. HCl is a
well known acid. Hydrochloric acid
• More complex Acids come from nonmetal binary
compounds. For example SO2 becomes the acid
H2SO3 (sulfurous acid). Just add water.
• Distinct from SO3 (sulfur trioxide) becomes
H2SO4 (sulfuric acid) a well known acid in water.
• Take any binary compound of a non metal and
oxygen and add water, and you get an acid (or two
distinct) acids (an oxyacid)
Specific Molecules You need to know
• Rather than continue with the full strategy
of naming all compounds lets focus on
molecules we will need to discuss reactions.
• Already done Col 1 and 2 with Cols 6 and
7, extend this to include Col 5.
• Now name specific molecules and anions
that use nonmetals.
Common Molecules and Names
• Notice H with non-metals make acids.
• HF, HCl, HBr, HI
• Ammonia, Methane, Water, HF
– CH4, NH3, H2O, HF
• Related ions
• Hydronium Ion, Hydroxide Ion, Ammonium Ion
H3O+ (or H+)
OH-
NH4+
• Oxides of non-metals are also acids.
– Contrast this with the oxides of metals (CaO) become
bases in water (Ca(OH)2)
• N, P, and S, Cl form oxides.
Oxides of Nonmetals
Acids and associated anions
Name
Formula
Hydrochloric acid
HCl
Hypochlorous acid
HClO
Chlorous acids
HClO2
†Chloric acid
HClO3
Perchloric acid
HClO4
Anion
Name
Cl−
Chloride ion
ClO− Hypochlorite ion
ClO2−
Chlorite ion
ClO3−
Chlorate ion
ClO4− Perchlorate ion
Common Oxyacids and Salts
Common molecules to name and recognize
Acid Molecules
What is common that makes the acid?
Ethyl Alcohol and Dimethyl Ether
Other molecules that use H, O and C, but are
not acids.
Examples of Names and Formulas of
Oxoanions and Their Compounds - I
• KNO2
BaSO3 barium sulfite
• Mg(NO3)2 magnesium nitrate
Na2SO4
• LiClO4 lithium perchlorate
Ca(BrO)2 calcium hypobromite
• NaClO3
Al(IO2)3
• RbClO2 rubidium chlorite
• CsClO
aluminum iodite
KBrO3
LiIO4 lithium periodate
Examples of Names and Formulas of
Oxoanions and their Compounds - II
• calcium nitrate
• strontium sulfate SrSO4
ammonium sulfite
lithium nitrite
• potassium hypochlorite KClO
lithium perbromate
• rubidium chlorate
calcium iodite
• ammonium chlorite NH4ClO2
• sodium perchlorate
(NH4)2SO3
LiBrO4
Ca(IO2)2
boron bromate
magnesium hypoiodite Mg(IO)2
Determining Names and Formulas of
Anions and Acids
Problem 6-4: Name the following anions and give the names and
a) I -
formulas of the acid solutions derived from them:
b) BrO3c) SO3 2- d) NO3e) CN -
Solution:
a) The anion is
b) The anion is bromate; and the acid is bromic acid, HBrO3
c) The anion is
d) The anion is nitrate; and the acid is nitric acid, HNO3
e) The anion is
Salts of Oxyacids: Example P
• Make an oxide of Phosphorous:
– O needs 2 electrons P gives 3
• Simplest possible one is P2O3 (di)Phosphorous(III) trioxide
• Next one up is: P2O5: (di)Phosphorous(IV) Pentoxide
• Add water:
P2 O3 + 3H 2O → 2 H 3 PO3
P2 O5 + 3H 2O → 2 H 3 PO4
– Phosphorous acid and Phosphoric acid
• Make Salt: Replace H with Na
– (tri)Sodium phosphite and sodium phosphate
Na3 PO3
Na3 PO4
Summary
Start learning these boldface ones.
Determining Names and Formulas of Binary
Covalent Compounds
Problem 6-5: What are the name or chemical formulas of the
following chemical compounds:
a) carbon dioxide b) PCl3 c) Give the name and chemical formula
of the compound formed from two P atoms and five O atoms.
Solution:
a) carbon dioxide
b) PCl3
c) The compound formed from two P atoms and five O atoms
Practice Problem 6-3
Determining Names and Formulas of Ionic
Compounds Containing Polyatomic Ions
a) magnesium perchlorate
b) (NH4)2SO3
c) calcium nitrate
d) Postassium permanganate
Practice: Find these Metals in Periodic Table
• Alkali metals - (lithium, sodium, potassium, rubidium and
cesium) - soft, low melting points, react with water to
liberate hydrogen, form 1:1 compounds with chlorine.
• Alkaline earths - (beryllium, magnesium, calcium,
strontium, barium and radium) - react in a 1:2 ratio with
chlorine. (Type I in text)
• Transition metals - (e.g. iron, copper, silver, gold, tungsten
and cobalt) - structural metals. Multi-valence; (Type II in
text)
• Actinides and Lantanides: Often multi-valence
• Metalloids - (antimony, arsenic, boron, silicon and
tellurium) - intermediate between metals and nonmetals.
Acts as metals with non-metals; Act as non-metals with
metals.
Answers to Some Problems in Lecture
1. (b) ZnCl2 , Zinc Chloride; (d) Sr3N2 , Strontium Nitride;
(f) Sc2S3 , Scandium Sulfide
2. (b) Cobalt (II) Fluoride; (d) Nickel (III) Chloride
3. (a) Mg( ClO4)2 ; (b) Ammonium Sulfite; (c) Ca(NO3)2
4. (a) iodide, hydroiodic acid, HI; (c) sulfite, sulfurous acid,
H2SO3 (e) cyanide, hydrocyanic acid, HCN
5. (a) CO2 ; (b) phosphorous trichloride; (c) diphosphorous
pentaoxide
NAMING OXOANIONS - EXAMPLES
per
hypo
Root
Suffixes
“
”
ate
“
”
ate
“
”
ite
“
”
ite
Chlorine
Bromine
Iodine
perchlorate perbromate periodate
[ ClO4-]
[ BrO4-]
[ IO4-]
No. of O atoms
Prefixes
chlorate
[ ClO3-]
bromate
[BrO3-]
iodate
[ IO3-]
chlorite
[ ClO2-]
bromite
[ BrO2-]
iodite
[ IO2-]
hypochlorite hypobromite hypoiodite
[ BrO -]
[ IO -]
[ ClO -]