Bonding And Intermolecular Forces Flashcards
Reactivity of covalent and ionic bonds determine…
the chemistry of a substance
The physical properties of a substance are determined by
the molecular level of the substance
Lewis Dot Structure: electrons in d subshell are not considered
valence electrons for transition metals since valence electrons are in the highest n level
Lewis Dot Structure represents?
accounts for the number and location of all valence electrons gives the sense of their reactivity
Octet is achieved for what?
the stabilize the atom (both of them)
Single Bond?
a bond formed from two electrons
Lone pairs are important for
determining the structure of the atom, physical properties
Double Bond?
four electrons
Triple Bond?
six electrons
What is Formal Charge?
a way to evaluate a proposed lewis dot structure and determine the sequence of atoms in a compound (when there is more then two atoms in a molecule).
-formal charge tells us if the atoms are sharing their valence electrons in the best way, which is when all charges equal zero.
What is the formula for Formal Charge?
FC=V-1/2B-L
V= valence electrons B= bonded (all the electrons present in the bond) L= lone pairs
What if the Formal Charge for all possible arrangements of the atoms in not zero?
Pick the one with the minimal charges
-the best structures have negative formal charges because more electronegative.
What are Resonance Structures?
A more accurate way of showing the electron distribution of atoms when the Lewis Dot Structure fails (this is normally when 2 of the same atoms are around the different center atom and their is one different bond present)
ex. O-S=O
(also shows the formal charge the same in both different ways)
What is a Resonance Hybrid?
Shows the two or more resonance structures averaged together because these resonance structures are all occurring at the same time.
- this is why the bonds (despite being different types) are the same length
- weighted average, meaning another resonance structure can be less important than the other, this is usually the case when the formal charge is not zero
Resonance structures are two or more structures where:
A. only atom may move around
B. only bonding electrons may move around
C. only nonbonding electrons may move around
D. only nonbonding electrons, and double and triple bonds may move around
D (important of ORGANIC)