Chem Naming Conventions

How are all ionic compounds named?

Name the positive ion (cation) first and the negative ion (anion) second.

How do you recognize a binary ionic compound?

It contains two elements and is typically a metal combined with a nonmetal.

How do you name a binary ionic compound?

Name the metal first, then use the root of the nonmetal followed by -ide.

How is a monatomic cation named?

Use the name of the element unchanged.

How is a monatomic anion named?

Use the root of the element name followed by -ide.

What ending is used for a monatomic anion?

-ide

What must the overall charge of an ionic compound equal?

Zero; the total positive and negative charges must balance.

How are subscripts determined in an ionic formula?

Use the smallest whole-number ratio of ions that gives the compound a net charge of zero.

Is a subscript of 1 written in a chemical formula?

No. A subscript of 1 is understood and is not written.

Are ion charges written in the final formula of an ionic compound?

No. Charges are used to determine the formula but are not written in the final compound formula.

What happens if the subscripts in an ionic formula have a common factor?

Reduce them to the smallest whole-number ratio.

Are numerical prefixes such as mono-, di-, and tri- used to show the number of ions in an ionic compound?

No.

When is a Roman numeral used in the name of an ionic compound?

When the metal can form more than one type of ion.

What does the Roman numeral in an ionic compound name represent?

The charge of the metal cation.

Does the Roman numeral tell you the number of metal atoms?

No. It indicates the charge of the metal ion.

Where is the Roman numeral placed in an ionic compound name?

Immediately after the metal name in parentheses.

How do you determine the Roman numeral for a variable-charge metal?

Use the charge of the anion and the requirement that the compound have zero net charge to determine the metal ion's charge.

Do metals that form only one common ion require a Roman numeral?

No.

What does -ous indicate in the older/common naming system for metal ions?

The ion with the lower charge.

What does -ic indicate in the older/common naming system for metal ions?

The ion with the higher charge.

How do you name an ionic compound containing a polyatomic ion?

Name the cation first and then use the established name of the polyatomic ion.

Does the name of a polyatomic ion change when it is part of an ionic compound?

No. Keep the polyatomic ion's established name.

How is a polyatomic ion treated when writing an ionic formula?

Treat the entire polyatomic ion as one charged unit.

When are parentheses used around a polyatomic ion in a formula?

When more than one of that polyatomic ion is required.

Are parentheses used when only one polyatomic ion is present?

No.

What is an oxoanion (oxyanion)?

A polyatomic anion in which an element, usually a nonmetal, is bonded to one or more oxygen atoms.

For a family with two oxoanions, what ending does the ion with more oxygen use?

-ate

For a family with two oxoanions, what ending does the ion with fewer oxygen use?

-ite

How are -ate and -ite related in the same oxoanion family?

The -ate ion has more oxygen atoms than the -ite ion.

What is the four-member oxoanion naming order from most oxygen to least oxygen?

per-...-ate → ...-ate → ...-ite → hypo-...-ite

What does per-...-ate indicate in a four-member oxoanion family?

The ion with the most oxygen atoms.

What does -ate indicate in a four-member oxoanion family?

The ion with one fewer oxygen atom than the per-...-ate ion.

What does -ite indicate in a four-member oxoanion family?

The ion with two fewer oxygen atoms than the per-...-ate ion.

What does hypo-...-ite indicate in a four-member oxoanion family?

The ion with the fewest oxygen atoms.

What is a hydrate?

An ionic compound containing a specific number of water molecules in each formula unit.

How are water molecules shown in the formula of a hydrate?

After a centered dot followed by the number of H₂O molecules.

How is a hydrate named?

Name the ionic compound first, then add a Greek numerical prefix followed by the word hydrate.

Prefix for 1

mono-

Prefix for 2

di-

Prefix for 3

tri-

Prefix for 4

tetra-

Prefix for 5

penta-

Prefix for 6

hexa-

Prefix for 7

hepta-

Prefix for 8

octa-

Prefix for 9

nona-

Prefix for 10

deca-

What are the two common types of acids in Section 2.8?

Binary acids and oxoacids.

What is a binary acid?

An acid formed from hydrogen combined with an anion whose name ends in -ide.

How is a binary acid named?

hydro- + nonmetal root + -ic acid

How does an -ide anion name change when forming a binary acid?

Use hydro- before the root and change the ending to -ic acid.

What is an oxoacid?

An acid derived from an oxygen-containing anion called an oxoanion.

How does an oxoanion ending in -ate change when it becomes an acid?

-ate changes to -ic acid.

How does an oxoanion ending in -ite change when it becomes an acid?

-ite changes to -ous acid.

Acid naming conversion for -ate

-ic acid

Acid naming conversion for -ite

-ous acid

Are the prefixes per- and hypo- retained when an oxoanion becomes an oxoacid?

Yes.

Is hydro- used when naming an oxoacid?

No.

What type of elements typically form binary covalent compounds?

Two nonmetals.

How can you distinguish binary covalent naming from binary ionic naming?

Binary covalent compounds typically contain two nonmetals and use numerical prefixes; binary ionic compounds typically contain a metal and a nonmetal and do not use numerical prefixes.

Which element is named first in a binary covalent compound?

Usually the element with the lower group number on the periodic table.

How is the second element named in a binary covalent compound?

Use its element root followed by -ide.

If both elements in a binary covalent compound are in the same periodic-table group, which is named first?

The element with the higher period number, meaning the element lower on the periodic table.

What is the oxygen-halogen exception for binary covalent naming?

When oxygen is combined with chlorine, bromine, or iodine, the halogen is named first.

How are the numbers of atoms indicated in a binary covalent compound?

Use Greek numerical prefixes.

When does the first element of a binary covalent compound receive a numerical prefix?

Only when more than one atom of the first element is present.

Is mono- normally used for one atom of the first element in a binary covalent compound?

No.

Does the second element of a binary covalent compound normally receive a numerical prefix?

Yes, including mono- when there is one atom.

What can happen to the final vowel of a numerical prefix before oxide?

The final vowel may be dropped to make the name easier to pronounce.

What is a hydrocarbon?

A compound containing only carbon and hydrogen.

What is an alkane?

The simplest type of hydrocarbon.

How are straight-chain alkanes named?

Use a root based on the number of carbon atoms followed by the suffix -ane.

Alkane root for 1 carbon

meth-

Alkane root for 2 carbons

eth-

Alkane root for 3 carbons

prop-

Alkane root for 4 carbons

but-

Alkane root for 5 carbons

pent-

Alkane root for 6 carbons

hex-

Alkane root for 7 carbons

hept-

Alkane root for 8 carbons

oct-

Alkane root for 9 carbons

non-

Alkane root for 10 carbons

dec-