General Chemistry 2.8

What are common names?

When chemistry was an infant science, there was no system for naming compounds. Names
such as sugar of lead, blue vitrol, quicklime, Epsom salts, milk of magnesia, gypsum, and
laughing gas were coined by early chemists. Such names are called common names.

Approximately how many chemical compounds are currently known?

5 million

What are organic compounds?

compounds based on chains
of carbon atoms

What are binary compounds?

compounds
composed of two elements

What are binary ionic compounds?

contain a positive ion (cation) always written first in the formula
and a negative ion (anion).

What are the rules for naming basic binary ionic compounds?

1. The cation is always named first and the anion second.
2. A monatomic (meaning "one-atom") cation takes its name from the name of
the element. For example, Na is called sodium in the names of compounds
containing this ion.
3. A monatomic anion is named

Name the following compound and describe the ions present: NaCl

Na+, Cl- Sodium chloride

Name the following compound and describe the ions present: KI

K+, I- Potassium iodide

Name the following compound and describe the ions present: CaS

Ca2+, S2- Calcium sulfide

Name the following compound and describe the ions present: Li3N

Li+, N3- Lithium nitride

Name the following compound and describe the ions present: CsBr

Cs+, Br- Cesium bromide

Name the following compound and describe the ions present: MgO

Mg2+, O2- Magnesium oxide

Name the following cations and anions: H+ H-
Li+ F-
Na+ Cl-
K+ Br-
Cs+ I-
Be2+ O2-
Mg2+ S2-
Ca2+ N3-
Ba2+ P3-
Al3+

Hydrogen Hydride
Lithium Fluoride
Sodium Chloride
Potassium Bromide
Cesium Iodide
Beryllium Oxide
Magnesium Sulfide
Calcium Nitride
Barium Phosphide
Aluminum

What is the formula for each of these: Hydrogen Hydride
Lithium Fluoride
Sodium Chloride
Potassium Bromide
Cesium Iodide
Beryllium Oxide
Magnesium Sulfide
Calcium Nitride
Barium Phosphide
Aluminum

H+ H-
Li+ F-
Na+ Cl-
K+ Br-
Cs+ I-
Be2+ O2-
Mg2+ S2-
Ca2+ N3-
Ba2+ P3-
Al3+

What is the difference between type I and type II binary ionic compounds as the textbook describes them?

(Type I) the metal present forms only
a single type of cation. Type II: In a case such as this, the charge on the metal ion
must be specified. The systematic names for these two iron compounds are iron(II) chloride
and iron(III) chloride, respectively, wh

Name:
Fe3+
Fe2+
Cu2+
Cu+
Co3+
Co2+
Sn4+
Sn2+
Pb4+
Pb2+
Hg2+
Hg2^2+
Ag+
Zn2+
Cd2+

Iron(III)
Iron(II)
Copper(II)
Copper(I)
Cobalt(III)
Cobalt(II)
Tin(IV)
Tin(II)
Lead(IV)
Lead(II)
Mercury(II)
Mercury(I)
Silver
Zinc
Cadmium

Write the chemical symbol for each:
Iron(III)
Iron(II)
Copper(II)
Copper(I)
Cobalt(III)
Cobalt(II)
Tin(IV)
Tin(II)
Lead(IV)
Lead(II)
Mercury(II)
Mercury(I)
Silver
Zinc
Cadmium

Fe3+
Fe2+
Cu2+
Cu+
Co3+
Co2+
Sn4+
Sn2+
Pb4+
Pb2+
Hg2+
Hg2^2+
Ag+
Zn2+
Cd2+

What is the older system of naming type II binary ionic compounds?

used for metals that form only two ions. The ion with the higher charge has a name
ending in -ic, and the one with the lower charge has a name ending in -ous.

Where do the following usually occur on the periodic table: where more than one ionic compound forms between a given pair of elements.

transition metals, which often form more than one cation

Silver is a transition metal. Is it named with a Roman numeral the way other transition metals are or is it an exception. And zinc?

although
silver is a transition metal (and can potentially form ions other than Ag+), silver
compounds are usually named without a Roman numeral. Thus AgCl is typically called
silver chloride rather than silver(I) chloride, although the latter name is tec

In terms of using roman numerals to name multiple possibilities for cations in the transition metals, what are the two main exceptions?

zinc, usually forms Zn2+; and silver usually forming Ag+

What is the rule for polyatomic ionic compounds?

They must be memorized

What are oxyanions?

anions that contain an atom of a given element
and different numbers of oxygen atoms.

What's the rule for naming polyatomic ions when there are two oxyanions or maybe even more than two oxyanions?

When there
are two members in such a series, the name of the one with the smaller number of oxygen
atoms ends in -ite and the name of the one with the larger number ends in -ate�for
example, sulfite (SO3^2-) and sulfate (SO4^2-). When more than two oxyani

Hg2^2+

Mercury(I)

NH4+

Ammonium

NO2-

Nitrite

NO3-

Nitrate

SO3^2-

Sulfite

SO4^2-

Sulfate

HSO4-

Hydrogen sulfate
(bisulfate is a widely
used common name)

OH-

Hydroxide

CN-

Cyanide

PO4^3-

Phosphate

HPO4^2-

Hydrogen phosphate

H2PO4-

Dihydrogen phosphate

NCS- or SCN-

Thiocyanate

CO3^2-

Carbonate

HCO3-

Hydrogen carbonate
(bicarbonate is a widely
used common name)

ClO- or OCl-

Hypochlorite

ClO2-

Chlorite

ClO3-

Chlorate

ClO4-

Perchlorate

C2H3O2-

Acetate

MnO4-

Permanganate

Cr2O7^2-

Dichromate

CrO4^2-

Chromate

O2^2-

Peroxide

C2O4^2-

Oxalate

S2O3^2-

Thiosulfate

What are the type III binary covalent compounds?

Compounds formed between two nonmetals

What are the rules for naming binary covalent compounds?

1. The first element in the formula is named first, using the full element name.
2. The second element is named as if it were an anion.
3. Prefixes are used to denote the numbers of atoms present. These prefixes are
given in Table 2.6.
4. The prefix mono-

Describe the Prefixes Used to
Indicate Number
in Chemical Names

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

What is the common name of N2O? Systematic name?

Systematic Name: dinitrogen monoxide Common Name: nitrous oxide

What is the common name of NO? Systematic name?

Systematic name: Nitrogen monoxide Common name: Nitric Oxide

Give the systematic name of the following: NO2
N2O3
N2O4
N2O5

Nitrogen dioxide
Dinitrogen trioxide
Dinitrogen tetroxide
Dinitrogen pentoxide

In naming binary covalent compounds, when do you drop the "a" or "o" of the prefixes?

when the element begins with a vowel. For example,
N2O4 is called dinitrogen tetroxide, not dinitrogen tetraoxide, and CO is called carbon
monoxide, not carbon monooxide.

What are three examples of compounds that are always referred to by their common names?

Three examples are
water, ammonia, and hydrogen peroxide. The systematic names for H2O, NH3, and H2O2
are never used.

How do you recognize if something is an acid?

Acids can be recognized by the hydrogen
that appears first in the formula.

HF

Hydrofluoric acid

HCl

Hydrochloric acid

HBr

Hydrobromic acid

HI

Hydroiodic acid

HCN

Hydrocyanic acid

H2S

Hydrosulfuric acid

HNO3

Nitric acid

HNO2

Nitrous acid

H2SO4

Sulfuric acid

H2SO3

Sulfurous acid

H3PO4

Phosphoric acid

HC2H3O2

Acetic acid

What are acids?

When dissolved in water, certain molecules produce a solution containing free H ions
(protons). An acid is a molecule in which one or more H+ ions are attached to an anion.

What is the first question you need to ask yourself if you're naming acids?

Does the anion
contain oxygen?

When naming acids, if the anion doesn't contain oxygen, what do you do?

hydro-
+ anion root
+ -ic
hydro(anion root)ic acid

When naming acids, if the anion DOES contain oxygen, what do you do?

Check the ending
of the anion. If -ite, anion or element root
+ -ous
(root)ous acid
If -ate, anion or element root
+ -ic
(root)ic acid