Chapter 3: Flashcards
Textbook
What are structural formulas?
Formulas that are more descriptive than chemical formulas because they show us how atoms are bonded together
What is the stability of noble gases related to?
The number of electrons in the atom
How can atoms achieve stable electron numbers?
By sharing or transferring electrons
What are valence electrons?
Electrons in the outermost energy level of an atom
What is an ionic bond explained by?
The attraction between positive and negative ions resulting from the transfer of one or more valence electrons
What is a covalent bond explained by?
The attraction by the nuclei of atoms for valence electrons that they share between them
Why do only valence electrons matter for bonding?
Because electron that are closer to the nucleus are held more tightly and can’t be moved
What is an orbital?
A region of space around an atom’s nucleus where an electron may exist
What is a bonding electron?
A single electron in a orbital that is available to bond with another electron
What is a lone pair?
2 electrons occupying the same orbital
What are lewis symbols?
Electron diagrams that represent the number of valence electrons in an atom
What does the element symbol represent in a lewis diagram?
It represent the nucleus and all of the non-valence electrons
What is electronegativity?
The ability of an atom attract bonding electrons to it valence level
What cause covalent bonding?
When the electronegativities are both relatively high neither will win and the bonding electrons will be shared by both atoms
What does ionic bonding depend on?
If the electronegativities of 2 atoms have a large difference the atom with the larger electronegativity will take the electron
What is the overall charge on ionic compounds?
Neutral because of the way they arrange themselves
What shape do ionic compounds arrange themselves in?
A crystal lattice
What is metallic bonding?
If both atoms have relatively low electronegativities the atoms share valence electrons because they are not held very strongly by their atoms. The valence electrons act like a sea that holds the positivity
Why are molecular formulas different from ionic formulas?
Because they show how the atoms are bonded in molecular formulas
What is bonding capacity?
The maximum number of single covalent bonds that an atom can form. It is determined by the number of bonding electrons
What is a coordinate covalent bond?
When an atom donates 2 electrons to another atom so they both have 8
What is a molecular formula?
A type of formula that shows how the atoms are bonded. ex. CH3COOH
What does a lewis diagram show?
It shows how the valence electrons are bonded using dots
What does a structural formula show?
It uses lines to show how atoms are bonded
What is stereochemistry?
The study of 3D spatial configuration of molucules
What does VSEPR stand for?
Valence Shell Electron Pair Repulsion Theory
What is VSEPR theory based on?
The electrical repulsion of bonded and unbonded pairs in a molecule that aim to stay as far apart as possible
What do 2 bond pairs and 0 lone pairs form?
Linear
X - A - X
What do 3 bond pairs and 0 lone pairs form?
Trigonal Planar
X
l
A
/ \
X XWhat do 4 bond pairs 0 lone pairs form?
Tetrahedral
X
l
A
E | \
X W XWhat do 3 bond pairs 1 lone pair form?
Trigonal Pyramid
A
/ | \
/ | \
X W XWhat do 2 bond pairs and 2 lone pairs form
Angular
What does 1 bond pairs and 3 lone pairs form?
Linear
How is the rate that hydrocarbons react affected by bonds?
- Hydrocarbons with multiple bonds react very quickly
- Hydrocarbons with single bonds react slowly
What is a polar molecule?
A molecule in which the negative charge is not distributed evenly
What are the polar molecules?
- Different atoms together
- Nitrogen and other atoms
- Oxygen and other atoms
- Carbon and two other kinds of atoms
What are the non-polar molecules?
- All elements
- Containing carbon and one type of other molecule
When will a nonpolar covalent bond be formed?
When 2 atoms have the same electronegativity so they share electrons equally
When will atoms form a polar covalent bond?
When they have different electronegativities and do not share electrons equally
What is a bond dipole?
The charge separation that occurs when there is an electronegativity difference
What are intermolecular forces?
The forces of attraction and repulsion between molecules
What are intramolecular forces?
The forces within a molecule
What are the 2 Van Der Waals forces?
Dipole-Dipole force
London Force
What are dipole-dipole forces?
Attraction between the positive and negative ends of polar molecules. They are very weak
What are london forces?
Momentary dipole-dipole forces that occur when electron distribution is momentarily uneven
How are electrons and boiling points related?
The lesser amount of electrons means the lower boiling point because it is easier to separate bonds
What is hydrogen bonding?
An intermolecular force when a hydrogen nucleus could be shared between electrons on adjacent molecules
What three atoms can be used in hydrogen bonding?
Nitrogen
Oxygen
Fluorine
