Brainscape's Knowledge GenomeTM

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


See full index

Organic Chemistry > Test 1 > Flashcards

Test 1 Flashcards

0
Q

What is the electronegativity difference of an ionic bond?

A

Greater than 1.9

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

What is the electronegativity difference of a polar covalent bond?

A

0.5-1.9

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

What is the electronegativity difference of a nonpolar covalent bond?

A

Less than 0.5

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

How do you determine formal charge?

A

Valence electrons on periodic table minus # of bonds and lone electrons in molecule

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

How do the melting points and boiling points of ionic substances compare to covalent substances?

A

Ionic substances have high melting and boiling points

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

what determines a molecular substances physical properties?

A

types and strengths of intermolecular forces

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

what are three types of intermolecular forces?

A

dispersion forces
dipole-dipole forces
hydrogen bonding forces

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

what is a protic solvent?

A

a solvent that donates a hydrogen bond

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

what is an aprotic solvent?

A

a solvent that cannot serve as a hydrogen-bond donor

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

what is a polar solvent?

A

a solvent with a dielectric constant of 15 or greater

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

what is a nonpolar solvent?

A

a solvent with a dielectric constant less than 15

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

what is a dielectric constant?

A

a measure of a solvent’s ability to insulate opposite charges from one another

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

what two factors determine if a substance is a good solvent?

A
  1. separate solute particles (same type and strength of intermolecular forces)
  2. keep them separated (if ionic or polar molecules make up solute, requires a large dielectric constant)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is a bronsted-lowry acid

A

substance that donates a proton

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

what is a bronsted-lowry base?

A

accepts a proton

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

what is needs to be stable for a substance to be an acid?

A

anion (conjugate base)

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

what 5 factors stabilize the anion of an acid?

A
  1. more electronegative
  2. larger radius
  3. delocalization with resonance
  4. delocalization through electron withdrawing
  5. more s character (% of hybrid orbital that s constitutes)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is the inductive effect?

A

the polarization of the electron density of a covalent bond by the electronegativity of a nearby atom

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

define the acid dissociation constant

A

K = [A-][H3O+]/HA

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

How do you calculate PKeq?

A

pKha - PKbh+

acid minus conjugate acid, according to equation given

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

what must be true about PKeq for a reaction to be favorable?

A

it must be negative

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is the general formula for an alkane?

A

CnH2n+2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what are constitutional isomers?

A

compounds with the same molecular formula but a different connectivity of their atoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is a bicycloalkane?

A

an alkane containing two rings that share two carbons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

how do you name a bicycloalkane

A

bycyclo[# of nonshared carbons in big ring. # of nonshared carbons in small ring. # of bridge carbons]suffix of total carbons-ane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is a conformation

A

an arrangement of atoms that results from rotation about a single bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what is strain?

A

instability within a structure that results in a higher internal energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what is a staggered conformation?

A

a conformation where atoms are as far apart as they can be

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what is torsional strain?

A

strain associated with not being in the minimum energy staggered conformation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what is an anti conformation

A

largest groups are 180 degrees apart

30
Q

what is a gauche conformation?

A

groups on carbon atom are 60 degrees apart

31
Q

what is angular strain?

A

any deviation from the hybrid atomic orbital’s normal angles

32
Q

what is steric strain?

A

any structural conformation where nonbonded atoms or groups are closer than the sum of their radii

33
Q

What is the predicted angle for sp hybridization?

A

180 degrees

34
Q

what is the predicted angle for sp2 hybridization?

A

120 degrees

35
Q

what is the predicted angle for sp3 hybridization?

A

109 degrees

36
Q

what is an eclipsed conformation?

A

a conformation when the groups on one carbon are as close as possible to the groups on adjacent carbon

37
Q

what is a dihedral angle

A

the angle between two planes that intersect carbon and a carbon-attached group.

38
Q

what is energy a function of in a torsional energy diagram

A

dihedral angle

39
Q

how does isopropyl alkyl group relate to isobutyl and isopentyl alkyl groups?

A

the CH(CH3)2 isopropyl group is attached to CH2 in isobutyl and a (CH2)2 group in isopentyl

40
Q

what are the common names of three carbon alkyl groups

A
  1. propyl

2. isopropyl

41
Q

what are the names of four carbon alkyl groups

A
  1. n-butyl
  2. sec-butyl
  3. tert-butyl
  4. isobutyl
42
Q

How does branching in constitutional isomers affect melting/boiling points?

A

branching decreases surface area which decreases dispersion forces and therefore melting/boiling points

43
Q

how does branching of constitutional isomers effect heat of combustion?

A

branching increases stability so it decreases heat of combustion

44
Q

what is heat of combustion?

A

heat released when one mole of a substance in its standard state is burned; associated with internal energy

45
Q

what is the primary strain in cyclopropane?

A

angular strain from compressing 109.5 degree bond angles to 60 degrees

46
Q

what is small ring strain?

A

a strain associated with ring sizes below 6 carbons arising from non-optimal bond angles

47
Q

why does cyclopropane have high torsional strain?

A

it is planar so it has 6 pairs of eclipsed C-H bonds

48
Q

2 ways rotating C-C bonds in a cycloalkane affects strain energy

A
  1. decreases torsional strain from eclipsed interactions

2. increases angular strain

49
Q

why is chair conformation of cyclohexane so favorable?

A

minimal angular strain and all C-C bonds are staggered

50
Q

why is twist-boat cyclohexane favorable to boat?

A

the twist relieves the torsional strain from the four pairs of eclipsed C-H interactions and the steric strain from “flag pole” hydrogens

51
Q

what is a 1,3 axial (diaxial) interaction?

A

steric strain arising from an axial substituent with another axial group on the same side of the ring

52
Q

why is envelope conformation favorable to planar cyclopentane?

A

bending a carbon out of the plane relieves torsional strain from 10 pairs of eclipsed C-H, even though angular strain is added by reducing angle from 108 to 105

53
Q

how does the size of a substitute group effect the conformation of cyclohexane?

A

the bigger the group, the more it will favor equatorial position

54
Q

what happens when large substitute groups like tert-butyl can’t avoid being in axial position?

A

most abundant conformation will be twist-boat

55
Q

what are substitution placements for cis 1,2 cyclohexane?

A

equatorial AND axial

56
Q

what are the substitution placements of trans 1, 2 cyclohexane?

A

diaxial OR diequatorial

57
Q

what are the substitution placements of cis 1,3 cyclohexane?

A

diaxial OR diequatorial

58
Q

what are the substitution placements of trans 1,3 cyclohexane

A

equatorial AND axial

59
Q

what are the substitution placements of cis 1,4 cyclohexane

A

equatorial AND axial

60
Q

what are the substitution placements of trans 1,4 cyclohexane

A

diaxial OR diequatorial

61
Q

what are four factors affecting reaction rate?

A
  1. collision frequency
  2. proper orientation
  3. availability of sufficient energy
  4. temperature
62
Q

Why is fluorine not used in halogenation reaction?

A

reacts too quickly and violently

63
Q

why is iodine not used in halogenation reactions?

A

its activation energy is too high

64
Q

why does Br selectively halogenate tertiary carbons and chlorine doesn’t?

A

it has a large activation energy, by Hammond’s postulate the transition state looks like product and therefore has considerable free radical character. the free radical character is stabilized by hyperconjugation. chlorine transition state doesn’t have as much free radical character

65
Q

why is Cl more reactive than Br in halogenation?

A

Cl has a lower activation energy for rate determining step

66
Q

what is the change in enthalpy?

A

difference in energy between products and reactants in a reaction

67
Q

what is a transition state

A

higher energy point on a reaction path diagram

68
Q

what is an activated complex

A

chemical structure during transition state

69
Q

what is activation energy

A

difference in energy between transition state and reactants

70
Q

what is the chain initiation of halogenation

A

formation of radical halogen from nonradicals

71
Q

what is chain propagation of halogenation

A

reaction of radical intermediate and a molecule to give new radical intermediate and new molecule

72
Q

what is chain termination in halogenation?

A

radical couplings and disproportionation

73
Q

what is disproportionation

A

hydrogen is transferred from one radical to a radical of same species, making an alkane and the molecule that lost hydrogen uses the electron from its radical and the electron from hydrogen to form an alkene

Organic Chemistry (9 decks)

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