Naming and Lewis Structures Quiz Flashcards
Chemical Formula For An Ionic Compound
Represents one formula unit of that compound
Always reduce
Formula Unit
Simplest whole number ratio of tha compound’s cations and anions
Oxidation
The charge
Many transition elements have more than one possible oxidation state, some only have one
Fixed
Single known charge
Anions
Binary
Two elements
Ionic
Opposite charged ions
Monatomic Ions
One element ion
Cation Ionic Compounds
Always comes first
Keeps name
Anion Ionic Compounds
Always comes second
Change ending to -ide
Subscript
Small numbers to the lower right of symbols
Refers to whatever its following
One is never used
Used to make net charge equal to zero
Binary Polyatomic Ionic Compounds
Two metals
Metal to nonmetal
Polyatomic Ion
An ionic compound with more than two elements
An ion made up of more than one atom that acts as a single charged unit
Polyatomic Ion Doesn’t Start With Metal
Means positive
Process of Naming Polyatomic Ions
Same as binary compounds
Treat as one unit
Never change subscripts
Multivalent
More than one possible oxidation states
Many transition and p block metals are this way
Roman Numerals
Used to tell which cation is present in the compound
An ionic compound that contains a cation that is a metal with more than one oxidation state is named with this
Process of Roman Numerals
Metal is transition or p block
Then look at monatomic ion lost to see if it has more than one charge
Use roman numeral to identify charge
Covalent Naming Process
Name first element fully
First element uses a prefix besides mono-
Second elements always change ending to -ide
Always use a secomd element prefix
Covalent Prefixes
Mono-
Di-
Tri-
Tetra-
Penta-
Hexa-
Hepta-
Octa-
Nona-
Deca-
Acidic Naming Process
Starts with hydrogen
No oxygen use hydro-
Don’t say hydrogen or oxygen
Use other element or polyatomic ion
-ate to -ic
-ite to -ous
Find Number of Hydrogen Based On
Based on charge of anion
Binary Acid
An acid that contains only two elements
First is hydrogen
Second is nonmetal
Name always begins with hydro-
Root of second element’s name follows the prefix
Ends with -ic acid
Oxyacid
An acid that contains hydrogen and an oxygen anion
Based on the name of the polyatomic ion created
Never use hydro-
Oxyanion
Polyatomic ion that contains oxygen
Never use hydro-
Writing Acidic Formulas
No hydro- tells oxyacid
Change ending -ate to -ic and -ite to -ous
Write the symbols with their charges
All acids begin with H+1
Add the nonmetal
Crossover changes to subscript position
Reduce
Acids Are Molecules
Covalently bonded except when dissolved in water
Then, become ions
Co-
Together
-valent
Valence electrons
Covalent Bond
Chemical bond formed by the sharing of electrons between two atoms
Attracted to unpair electron neither can take it away
Molecule
Neutral group of atoms that are held together by covalent bonds
Molecular Compound
Chemical compound whose simplest units are molecules
Shared Electrons
Form overlapping orbitals so that each atom achieves the octet rule
Exceptions to the Octet Rule
Atoms that can not fit eight and atoms that can fit more than eight in valence level
Incomplete Octet
Hydrogen can only hold one more electron in its s orbital, only forms one bond
Boron has three valence electrons, so forms three bonds and is only surrounded by six electrons
Beryllium has two valence electrons, two bonds, surrounded by four
Expanded Octet
Involving more than eight electrons
P
S
Xe
Can Form Covalent Bonds
Beryllium
Can Form Bonds With Expanded Octets
Main group elements in periods 3 and below
Lewis Structure Guide
Count total number of valence electrons for all atoms in the molecule
Set up skeletal structure with least electronegative as central
Give all atoms an octet besides incomplete
Count electrons to match the number electrons required
Exceptions to Central Atoms
Can bond central atoms together
Carbon is always central
Hydrogen is never
Halogens are almost never
Simple Lewis Rules
Count
Find middle
Set up
Make connections
Add to ends then middle
Count
HONC
Hydrogen and halogens form one bond never central atom
Oxygen forms two bonds can form double nonds
Nitrogen forms three bonds can form double or triple bonds
Carbon forms four bonds can form double or triple bonds
Exception to HONC
CO
Resonance
When a single Lewis structure does not clearly represent a covalently bonded molecule or ion
Shown with a double headed arrow
Carbon
Forms four bonds
Can form double or triple bonds
Seven Diatomic Elements
Bromine
Iodine
Nitrogen
Chlorine
Hydrogen
Oxygen
Fluorine
ABX Notation
Notation for the molecule that shows the number of lone pairs and bonding pairs as subscripts
X represents number of lone pairs
B represents number of bonding pairs
Lewis Dot for Single Atoms
1 top right
2 both right
3 right and top left
4 right, top left, and bottom left
5 right, top left, bottom left, and bottom right
6 right, top, bottom left, and bottom right
7 right, top, left, and bottom right
