Making Chemical Compounds
7.1 Chemical Names and Formulas
Review
• Ionic charges (groups of the periodic table)
• What makes up ionic compounds?
• What makes up molecular (or covalent)
compounds?
• Cation?
• Anion?
• Molecule?
• Chemical formula?
Making Ionic Compounds
• Ionic compounds are made up of a _______
and a _______.
• When making an ionic compound, the _______
is written first, then the ________.
• Write the ionic charge in the top right-hand
corner of the symbol.
• Criss-cross the charges (move the number of the
charge from the top right-hand corner to the
opposite bottom corner).
Examples
1.
2.
3.
4.
5.
6.
7.
Sodium and chlorine
Sodium and oxygen
Sodium and nitrogen
Magnesium and sulfur
Magnesium and phosphorus
Aluminum and bromine
Aluminum and oxygen
Naming Ionic Compounds
1. The name of the cation goes first
2. Drop the suffix (last syllable) of the anion, and
add –ide
1. For example, chlorine = chloride, sulfur =
sulfide
Examples
•
•
NaCl = Sodium chloride
CaO = Calcium oxide
▫
Practice individually on page 223, #2
Transition Metals
• Metals in groups 3-12 have more than one ionic
charge because of their mobile valence electrons
(remember the sea of electrons?)
• When naming these compounds, we will use the
Stock system.
• Put the number of the charge on the transition
metal as a roman numeral in parentheses.
▫ For example: Cu2+ = Copper (II), Sn4+ = Tin (IV)
• Practice individually on page 225, #1 and 2
Polyatomic Ions
• You must memorize the names and formulas of
the following polyatomic ions (p.226):
▫
▫
▫
▫
Acetate
Cyanide
Hydroxide
Permanganate
▫ The rest are provided on the back of your periodic
table
Compounds with Polyatomic Ions
• Polyatomic ions act as one unit when forming
compounds.
• They have one ionic charge (equal to the sum of
all of the individual atoms’ ionic charges)
• They will act as either a cation (NH4+) or an
oxyanion (ions with oxygen)
Examples
•
•
•
•
Sodium and hydroxide
Sodium and sulfate
Sodium and phosphate
Ammonium and nitrate
• Practice individually on page 227, #1
Naming Compounds with Polyatomic
Ions
• Polyatomic ions keep their name unaltered in
compounds
▫ This is because the suffix of a polyatomic ion
indicates the number of oxygens in the ion.
 Ex. Sulfate is (SO42-), but sulfite is (SO32-)
▫ In compounds with ammonium, single-atom
anions (like chlorine, sulfur, etc.) will change to
the –ide ending.
 Ex. Ammonium chloride is NH4Cl.
• Practice individually on page 227, #2
Making Molecular Compounds
• Molecular compounds
do NOT criss-cross their
charges.
• Molecules are named
using numerical prefixes
(p.228).
▫ Ex. Carbon dioxide is
CO2, because di- means
two.
• Practice together on
page 229, #1 and 2
Prefixes:
1= mono2 = di3 = tri4 = tetra5 = penta6 = hexa7 = hepta8 = octa9 = nona10 = deca-
Naming Acids
• Binary acids (H-anion) include the name of the
anion with hydro–ic acid.
▫ Ex. Hydrochloric acid is HCl
▫ What would Hydrosulfuric acid be?
• Oxyacids (H-oxyanion) include the name of the
polyatomic ion with the suffix –ic acid.
▫ Ex. Sulfuric acid is H2SO4
▫ What would nitric acid be?
You need to know:
• From the chart on page 230, you need to know
the following:
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▫
▫
▫
▫
▫
▫
▫
hydrofluoric acid
hydrochloric acid
hydrobromic acid
phosphoric acid
nitric acid
sulfuric acid
acetic acid
carbonic acid.
Homework
• Homework: Complete 7.1 section review NOW