Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

chem > Chem chapter 8 exam 4 > Flashcards

Chem chapter 8 exam 4 Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Chemistry flashcards Periodic Table flashcards Chemistry 101 flashcards Organic Chemistry 101 flashcards
1
Q

octet rule exceptions

A

odd-electron species
incomplete octet
expanded valance shell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

odd electron species (octet rule exception)

A

-an octet can’t be achieved if there are an odd-number of electrons in a compound
-they have free radicals, or an unpaired electron, which makes the atom/compound more reactive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

incomplete octet (octet rule exceptions)

A

boron is generally stable with 6 electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

expanded valance shell (octet rule exceptions)

A

-elements (the central atom) in row 3 or lower can expand their valance shell to hold more than eight electrons
-can help reduce formal charges`

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

in organic lewis structures, the carbons…

A

connect to each other and the non-carbons connect to the carbons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

electron geometry

A

the geometry of all of the atoms and the electrons in a compound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

molecular geometry

A

the geometry of the atoms in a compound (still affected by the lone pairs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

how to determine electron groups

A

how many bonding pairs and lone pairs there are
for example, in NH3, the lewis structure has 3 lines and 1 set of lone pairs on the central atom, so they have 4 electron groups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

2 electron groups

A

linear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

3 electron groups

A

trigonal planar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

4 electron groups

A

tetrahedral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

5 electron groups

A

trigonal bipyramidal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

6 electron groups

A

octahedral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

molecular geometry: linear with zero lone pairs

A

] linear
] 180 degrees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

molecular geometry: trigonal planar with zero lone pairs

A

] trigonal planar
] 120 degrees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

molecular geometry: trigonal planar with one lone pairs

A

] bent
] <120 degrees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

molecular geometry: tetrahedral with zero lone pairs

A

] tetrahedral
] 109.5 degrees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

molecular geometry: tetrahedral with one lone pairs

A

] trigonal pyramidal
] <109.5 degrees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

molecular geometry: tetrahedral with two lone pairs

A

] bent
] <109.5 degrees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

molecular geometry: trigonal bipyramidal with zero lone pairs

A

] trigonal bipyramidal
] 120 degrees, 90 degrees

21
Q

molecular geometry: trigonal bipyramidal with one lone pairs

A

] seesaw
] <120 degrees, 90 degrees

22
Q

molecular geometry: trigonal bipyramidal with two lone pairs

A

] T-shaped
] 180 degrees, 90 degrees

23
Q

molecular geometry: trigonal bipyramidal with three lone pairs

A

] linear
] 180 degrees

24
Q

molecular geometry: octahedral with zero lone pairs

A

] octahedral
] 90 degrees

25
Q

molecular geometry: octahedral with one lone pairs

A

] square pyramidal
] 90 degrees

26
Q

molecular geometry: octahedral with two lone pairs

A

] square planar
] 90 degrees

27
Q

when looking at a molecule with multiple central atoms, how can we find the electron geometry?

A

look at each central atom and count for lone and boding pairs

28
Q

no or very little difference in electronegativity (EN)

A

covalent

29
Q

moderate difference in EN

A

polar covalent

30
Q

large difference in EN

A

ionic

31
Q

ΔEN less than or equal to 0.4

A

covalent

32
Q

ΔEN between 0.4 and 1.8

A

polar covalent

33
Q

ΔEN greater than 1.8

A

ionic

34
Q

in a polar covalent bond, the bonds…

A

involve unequal sharing of electrons, which will result in partial charges
- the more EN will have more of a (-) charge and the less EN will have more of a (+) charge

35
Q

polar covalent bonds on pictures of the molecule

A

more blue means more (+) so less e-
more red means more (-) with means more e-

36
Q

a polar bond dosent always mean the molecule is polar because it requires a … and a polar bond creates a …

A

-it requires a net dipole moment
-a polar bond creates a dipole, but the molecular geometry can cancel it out

37
Q

for a polar molecule, there must be…

A
  • must have a polar bond
  • the polar bonds must not cancel out
    (usually happens when the electron and molecular geometry match)
    for example: o=c=o, the oxygens are more EN and pull on opposite sides of the carbon, but since there is a pull on both sides, they cancel out and the bond is non polar.
38
Q

bond order

A

the number of bonding electron pairs shared by two atoms in a molecule
- single bonds: 1
- double bonds: 2
-triple bonds: 3

39
Q

higher order bonds vs lower order bonds

A

higher order bonds: shorter and stronger
lower order bonds: weaker and longer bonds

40
Q

why do we get short order bonds

A

more electrons shared between two elements results in more overlap between the electron clouds thus shorter

41
Q

why do we have stronger order bonds

A

more electrons shared in bonds between two elements requires more energy to break thus stronger

42
Q

a single bond is

A

the longest and weakest

43
Q

a double bond is

A

in the middle with length and strength

44
Q

a triple bond is

A

the shortest and strongest

45
Q

bond length and atomic radii

A

when comparing between different pairs of elements depend on the atomic radii
- smaller elements make shorter bonds

46
Q

bond order formula=

A

(number of shared pairs in all X-Y bonds)/ (number of X-Y links in the molecule or ion)
or think of it as number of lines divided by the groups of lines

47
Q

average bond energy (KJ/mol)

A

the amount of energy to break a bond and these are endothermic since you need energy going into the compound to break the bond(s)

48
Q

heats or reaction to get average bond energies

A

Σ(BE reactants)- Σ(BE products)

49
Q

how can you tell if a reaction is endo or exothermic

A

-if the reactants have weak bonds and the products have strong bonds, exothermic
-if the reactants have strong bonds and the products have weak bonds, endothermic

chem (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions