Chapter 1 Flashcards
Atoms are made up of _______, _______, _______
protons, neutrons, and electrons
each element is distnguished by the number of _______ in the nucleus = _______
protons, atomic number
electrons are found in _______, which are grouped into different _______ found at different distances from the nucleus
orbitals, shells
the most common _______ elements are found in the first __ rows of the period table: electrons are found in just the first __ electron shells
organic, 2, 2
The first shell (n=1) consists of just the 1s orbital and can hold ___ electrons
2
the second shell (n=2) consists of the 2s, 2px, 2py, 2pz orbitals and can hold __ electrons
8
What principle states that an electron will fill the lowest energy orbital first
Aufbau’s principle
In ionic bonding, electrons are _______ from one atom to another in an attempt to fulfill their _______. The resulting Ions have _______ charges, which _______ each other
transferred, octet, opposite, attract
in covalent bonding, electrons are _______ between atoms in an attempt to fulfill their octet
shared
Octet rule: atoms desire to have a filled shell of electrons. A _______ shell means 8 valence elections. (exception H and He want __)
full, 2
What are the common bonding patterns of H, C, N, O, and Cl (halogens)
H: one bond
C: 4 bonds
N: 3 bonds, 1 lone pair
O: 2 bonds, 2 lone pairs
Cl (halogens): 1 bond, 3 lone pairs
A bonding pair of e- is symbolized by a pair of _______ or _______
dots, dash
lone pairs are _______ e- that are not shared between 2 atoms
nonbonding
Nonpolar covalent bonds have electrons which are shared _______ between the 2 atoms
equally
Polar covalent bonds have bonding electron which are shared _______ between two atoms
unequally
Formal charge =
group # - (nonbonding e-) - (1/2 shared e-)
group # - bats - balls
Some organic compounds contain _______ bonds
ionic
Some organic compounds can be drawn either _______ or _______
covalently or ionically
resonance = movement of _______ only! _______ cannot be moved
electrons
atoms
The negative charge is _______ (spread out) over both O1 and O2 atoms. Spreading the negative charge over two atoms makes the ion ______ stable than it would be if localized in only one atom. This is known as _______
localized
more
resonance stabilization
When can you draw resonance?
When an atom with a lone pair, positive charge, or negative charge is adjacent to a double or triple bond
*special: when atom with lone pair is next to atom with positive charge
Resonance rules:
1) resonance forms must be valid _______ for the compound and follow the _______ rule
2) move only ______, never move atoms
3) all _______ must remain the same
4) single bonds are very _______ and are rarely involved in resonance
5) the major resonance contributor is the one with the _______ energy and follow most important to least important
a) _____ satisfied
b) _____ charges
c) negative charges prefer _____ atoms
6) EN atoms can hold a _______ charge only if they have octets
7) more resonance structures = _______ energy
1) lewis structures, octet
2) electrons
3) bond angles
4) stable
5) lower
a) octets
b) minimize
c) EN
6) positive
7) lower
Condensed structural formula does not show all the individual _______
bonds
in structural formula, _______, _______, _______ are shown and H is invisible unless bonded to an atoms that is shown.
N
O
halogens
Atomic Orbitals can be described by its _______ which is the _______ description of the shape of the wave as it vibrates
wave function
mathematical
the square of the wave function tells us where the _______ is the highest
electron density
where is electron density highest for the s orbital
at the nucleus
2p atomic orbitals have __ lobes which are _______ and are seperated by a _______
2
out of phase (- and +)
node
the more nodes an orbital contains the _______ the energy
higher
atomic orbitals can combine to generate new, more complex, orbitals in a process called _______
linear combination of atomic orbitals
orbitals on _______ atoms interact to produce _______ that lead to bonding or antibonding interactions
different
molecular orbitals
orbitals on the _______ atom interact to produce ______ orbitals that define the geometry of the bonds
same
hybrid atomic orbitals
The stability of a covalent bond results from a large amount of electron density in the _______ region
bonding
in the bonding region, electrons are shared between the atoms and are close to both nuclei’s creating _______
molecular orbital
as 2 H’s with the same sign approach each other, their 1s orbital can add _______ to form a ______ bond
constructively
sigma
all single bonds are sigma bonds, and every double or triple bond contains __ sigma bond
1
all double bonds are pi bonds, and every triple bond contains __ pi bond
2
as 2 H’s with opposing signs approach each other, their 1s orbital can add _______ to form a ______ bond. The result is a _______ separating the 2 atoms
destructively
anti-bonding
node
Bonding MO have _______ energy compared to anti-bonding
lower
if electrons are found in the _______ MO the molecule likely won’t exist
anti-bonding
a pi bond result from the overlap between two p orbitals that are ________ to the line connecting the nuclei. This overlap is _______, not linear like a sigma bond
perpendicular
parallel
Hybrid atomic orbitals: mixing of orbitals on the _______ atom. Their geometry accounts for the actual structures and _______ angles observed in organic compounds
same
bond
electron pairs ______ each other and will adopt an arrangement that _______ repulsion
repel
minimizes
When resonance is possible, the _______ hybridization option will be the truth
lower
rotation about the _______ bond is allowed, but a _______ is rigid and cannot be twisted under normal conditions
single
double
Rotation of a _______ bond usually represents the same compound. This is an example of _______ isomerism.
single
conformational
Double bonds tend to be rigid, therefor the placement of the groups attached to the double bond matters and can result in_______ different compounds. what is an example?
two
cis and trans
Constitutional (structural) isomers: _______ molecular formula, _______ connectivity. The number of isomers _______ rapidly as the number of carbon atoms increase
same
different
increases
Stereoisomerisms: _______ molecular formula, ______ connectivity, _______ spatial orientation
same
same
different
