1. Naming Inorganic Compounds
UNIT IV
Naming Inorganic Compounds

2. Inorganic Nomenclature
nomenclature refers to ‘naming’
The periodic table organizes the elements by vertical groups (________________) and horizontal rows (__________________).
The elements are arranged in order of increasing atomic mass; chemical and physical properties form patterns that repeat at regular intervals.

3. IV.1 The Chemical Elements
Element symbol: The first letter is always in upper case and the second letter (if present) is always lower case.
3 Major classifications:
Non-Metals
Metals
Metalloids

4. IV.2 Naming Inorganic Compounds
Ion charges indicate whether atoms of an element want to lose electrons or gain electrons in order to have a full valence shell.
METALS: form __________________ions
Cation: an ion with a positive charge
NON-METALS: form ___________________ ions
(H is generally an exception)
Anion: an ion with a negative charge

5. IV.2 Naming Inorganic Compouds
Some other definitions:
MONATOMIC –
DIATOMIC –
TRIATOMIC –
POLYATOMIC –

6. IV.2 Naming Inorganic Compounds
 1. Naming Monatomic Ions:
A. NAMING MONATOMIC METAL IONS
use the name of the metal and add the word “ion”.
ex:
Stock System of naming metal ions:
If it is a multivalent metal (more than one charge for the ion), the charge is indicated by roman numerals in brackets.

7. IV.2 Naming Inorganic Compounds
Ex #1: Write the names of the following ions:
N3+ = __________________________
Ni2+ = __________________________
Ex #2: Write the formula of the following ions to show their charges:
Uranium (VI) ion = __________
Iron (II) ion = __________
Nickel (II) ion = __________

8. IV.2 Naming Inorganic Compounds
B. NAMING MONATOMIC NON-METAL IONS
take off the original ending and add an “ide” ending.
ex:
Ex #3: Write the names of the following ions:
a) Br- = __________________________
b) Cl- = __________________________
c) I- = __________________________
d) O2- = __________________________

9. IV.2 Naming Inorganic Compounds
2. Naming Polyatomic Ions:
What is a polyatomic ion?
Rules for naming are more complicated (we won’t learn them). But we will need to KNOW some common polyatomic ions (names, formula, charge).
** Know table on page 69.
In order to name compounds, we must know the names and chemical formulae of elements.
do self-test on page 66
do question # 1 on page 68

10. IV.2 Naming Inorganic Compounds
3. How to Write the Formula of an IONIC COMPOUND When Given the Name:
An ionic compound = a compound made up of ions.
the ions have charges but the compound is a neutral molecule.
example:
The chemical name of an ionic compound always gives the positive ion (cation) first and the negative ion (anion) second.

11. IV.2 Naming Inorganic Compounds
3 simple rules:
RULE
EXAMPLE
1. Write formula for positive ion first, then negative ion.
2. Swap & drop the numbers in front of the charges on the ions (if no number, use a 1).
3. Tidy it up. Reduce subscripts if both can be divided by 2. Omit any subscript that is a 1.
Potassium Iodide

12. IV.2 Naming Inorganic Compounds
Ex: Sodium chloride: sodium (Na+), chloride (Cl-)
Ex: Iron (II) sulphate: iron (II) (Fe2+), sulphate (SO42-)
Ex: Tin (IV) oxide: tin (IV) (Sn4+), oxide (O2-)
 Questions: p. 71 # 4 (odds)

13. IV.2 Naming Inorganic Compounds
4. How to Write the Chemical Name of an IONIC COMPOUND When Given the Formula: **Check your periodic table to see if the positive ion has more than one ion charge.

14. IV.2 Naming Inorganic Compounds
A) If the first ion has only one possible ion charge:
write the names of the ions one after the other
omit the word “ion”
ex: ZnCl2

15. IV.2 Naming Inorganic Compounds
B) If the first ion has more than one possible charge:
“Deswap and dedrop” the charges (find out the charge)
check the known charge on negative ion (double or triple charges if needed)
write the charge of the positive ion with roman numerals
ex: PbO2
ex: Cu2O

16. IV.2 Naming Inorganic Compounds
** Note: you must memorize the “common name” of 2 compounds:
H2O = water
NH3 = ammonia
Questions: p. 72 #5 (odds)

17. IV.2 Naming Inorganic Compounds
5. Naming Hydrates
Hydrates are ionic compounds that include water molecules in their crystal structures.
naming hydrates is pretty straightforward and relies on using prefixes to tell how many water molecules are attached.
the # of water molecules is shown after a centered dot

18. IV.2 Naming Inorganic Compounds
**see table of page 72 for prefixes
ex: MgSO4·7H2O
ex: LiNO3·3H2O
Questions: p. 73 #6 and 7

19. IV.2 Naming Inorganic Compounds
6. Naming COVALENT COMPOUNDS Using the Prefix-Naming System
Binary Compound: a compound made of two different types of atoms (usually non-metals)
use the prefix-naming system
ex:
Tertiary Compound: a compound made of three different types of atoms.

20. IV.2 Naming Inorganic Compounds
RULES:
each compound name is made of words, each with a suitable prefix
see p. 73:
first word is the name of element with a prefix to indicate the # of atoms
second word is the name of the element with an “ide” ending and a prefix to indicate the # of atoms
Exception: if there is only ONE atom of the first element, don’t use the prefix mono. Ex: CO2 =

21. IV.2 Naming Inorganic Compounds
Examples:
P2S3 =
CO =
BrCl3 =
S2Cl2 =
Questions: p. 74 #8, 9 (odds)

22. IV.2 Naming Inorganic Compounds
7. Some Common Acids
A compound is called an acid when the chemical formula starts with ‘H’
ex: HCl, H2SO4
 (see common acids on p. 74 – KNOW THESE)

23. IV.3 Colours of Some Common Aqueous Ions
some ions have characteristics colours.
helpful in chemistry to be able to recognize these ions
(see table on p. 75 – KNOW)
Questions: p. 75 #10-13
Practice Questions
Naming - p. 75 # 15 – 65 (odds)
Formulas – p – 125 (odds)