ORGO Chapter 2-3

Which of these is the weakest of the intermolecular attractive forces? A) Ion-ion B) van der Waals C) Dipole-dipole D) Covalent bonding E) Hydrogen bonding

B

benzene

Consists of a ring of six carbon atoms with alternating single and double carbon-carbon bonds. c6h6 primary aromatic hydrocarbon

any diatomic molecules in which the two atoms are DIFFERENT (nd thus have differing EN) WILLL HAVE A

DIPOLE MOMENT

Deprotonation of Carboxylic Acids

Deprotonation of this functional group gives a resonance-stabilized anion in which the negative charge is spread over two oxygen atoms.

leveling effect

If a base stronger than HO- is dissolved in water, the base reacts with water to produce hydroxide. This is called the leveling effect. The inability of a solvent to distinguish the strength of an acid (or base) that is stronger than the conjugate acid (or conjugate base) of the solvent If a base stronger than HO- is dissolved in water, the base reacts with water to produce hydroxide. This is called the leveling effect.

guidelines for water solubility: for compounds containing one hydrophilic group ( and thus able to form strong hydrogen bonds), the follow approximate guidelines hold:

- compounds w/ 1-3 carbon atoms are water soluble -componds with 4-5 carbons are borderline soluble - compounds with six carbons + are insolubl

cyclic nitriles are named by adding the suffix -_______

-carbonitrile

pka

-logKa

ph =

-log[H3O+]

carboxylic acids (like acetic acid) usually have a pka of

3-5

carboxylic acids general pka

3-5

A non-zero dipole moment is exhibited by: A) SO2 B) CO2 C) CCl4 D) BF3

A

The solid alkane CH3(CH2)18CH3 is expected to exhibit the greatest solubility in which of the following solvents? A) CCl4 B) CH3OH C) H2O D) CH3NH2 E) HOCH2CH2OH

A

kekule structure

A classical structural formula for an aromatic compound, showing localized double bonds. structure resembling benzene's c6h6 structure. there is much evidence that proves this structure as incorrect if benzene had alternating single and double bonds as the Kekule structure indicates, we would expect the lengths of the carbon-carbon bonds around the ring to be alternately longer and shorter in fact, the c-c bonds of benzene are all the same lengths (a value in between that of a c-c single bond and a c=c double bond solution: resonance structures

ACID STRENGTH IS CHARACHTERIZED IN TERMS OF

ACIDITY CONSTANT (Ka) or pKa values

acetylene vs ethylene which one is more acidic

Acetylene (H-C≡C-H) is more acidic. The conjugate base of acetylene has a negative charge associated with a lone pair in an sp hybridized orbital, which is more stable than a negative charge associated with a lone pair in an sp2 hybridized orbital.

baking powder

It is a powder mixture that contains both sodium bicarbonate and an acid salt, such as potassium bitartrate: a mixture of sodium bicarbonate and cream of tartar, used instead of yeast in baking

strong bases

LiOH, NaOH, KOH, RbOH, CsOH, Ca(OH)2, Sr(OH)2, Ba(OH)2

sodium bicarbonate

NaHCO3

A molecule with a dipole moment is a

POLAR MOLECULE

ethers

R-O-R or may be R-O-R' where R' may be a phenyl or alkyl group

alcohols

R-OH

amides

RCONH2, RCONHR', RCONRR'

bp of h20, HF, and NH3

REPECTIVELY, 100, 19.5, -33.4

endergonic reaction

Reaction that absorbs free energy from its surroundings. non spontaneous

solvent effects are invoked to explain small differences in pKa values . EXPLAIN THE SOLVATING EFFECT

Small pka can be explained by the solvating effect. some ions can be seen as sterically hindered (bulky) and is thus less capable of interacting with the solvent which makes it less stable.

is h2o of h2s more acidic

Sulfur and oxygen are in the same column of the periodic table (group 6A), so we must compare their size. Sulfur is larger than oxygen and can better stabilize the negative charge that will be generated upon deprotonation. Therefore, H2S is expected to be more acidic than H2O.

THE LARGER THE ATOM,

THe better it is to stabilize a negative charge (by spreading the charge over a larger volume)

which one is more acidic: ethanol or water

The CH3CH2 group in ethanol provides a small amount of steric bulk that is absent in water. As such, water is more acidic than ethanol (for the same reason that ethanol is more acidic than tert-butanol). Indeed, the pKa of water (15.7) is slightly lower than the pKa of ethanol (16).

Deprotonation

The removal of a hydrogen cation (H+) from a molecule

AMIDE

Where a carbonyl group is bonded to a nitrogen atom bearing hydrogen and/or alkyl groups

methylene group

a CH2 group

positive entropy change

a change from a more ordered system to less ordered

carbonyl group

a chemical group consisting of a carbon atom linked by a double bond to an oxygen atom

alkenyl halide

a compound with a halogen atom bonded to an alkene carbon

carbonyl group

a group where a carbon atom is linked by a double bond to an oxygen atom; if the carbon atom in the group is at the end of the carbon skeleton, it is called an aldehyde. If the group within a carbon chain is called ketones

aryl halide

a halocarbon in which one or more halogens are attached to the carbon atoms of an aromatic ring such as a benzene ring

Alkynes

a hydrocarbon compound with a carbon-carbon triple bond.

dipole

a molecule that has two poles, or regions, with opposite charges

benzyl alcohol

a primary alcohol (hydroxyl group attached to a primary carbon)

geraniol

a primary alcohol (hydroxyl group attached to a primary carbon)

Bronsted-Lowry base

a substance that can accept a proton proton acceptor

acid base reactions always favor the formation of

a weaker acid and the weaker base why? because the outcome of an acid base rxn is determined by the position of an equilibrium

endothermic

absorb heat have positive change in H (enthalpy) atoms have smaller enthalpy as reactants

some drugs are ___ and some are ____

acids; bases

thymine hydrogen bonds with

adenine

isopropyl alcohol

aka 2-propanol a secondary alcohol

acidity of alkyne, alkenes, and alkanes

alkyne hydrogen (ex. ethyne c2h2) is weakly acidic alkene (ex. ethene c2h4) and alkane (ex. ethane c2h6) are not acidic at all pka 25,44,50 respectively

electrophiles

all lewis acids reagents that seek electrons carbon atoms that are electron poor because of bond polarity but do not consider themselves carbocations

conjugate of carboxylic acid

always resonance stabilized

proteins contain

amide groups

strong acid

an acid that ionizes completely in aqueous solution HCl, HI, HBr, H2SO4 (Sulfuric acid), HNO4 (Nitric acid), HCLO4 (Perchloric acid)

aromatic compound

an organic compound that contains the benzene ring structure and may have a pleasant or unpleasant odor and flavor

When butane is deprotonated,

anegative charge is generated on a carbon atom

proton acidity increases from left to right in a given row on the table due to increasing stability of the base. explain this

as you go from L to R, electronegativity increases. and as you go right, the more polarized the H bond will be to the element (and the most positive the proton becomes), therefore the easier and more readily the proton will be lost and thus the more acidic.

why does basicity increase as you go left on the table

as you go left, the less EN elements get and the less able the element is to accept the negative charge (but can accept proton).

heteroatoms

atoms like oxygen, nitrogen, and sulfur that form covalent bonds and have unshared electron pairs Atoms in an organic compound other than carbon and hydrogen

dipole-dipole forces

attractions between oppositely charged regions of polar molecules most organic molecules have a permanent dipole moment resulting from a nonuniform distribution of bonding electrons

When an acidic compound is present in the dough or batter,

baking soda can be protonated, causing liberation of CO2

an sp3 carbanion is the strongest ___

base in a series based on carbon hydridization and an sp carbanion (an alkynide) is the weakeast base

why does ethanol have a higher boiling point that dimethyl ether

because ethanol has a hydrogen atom covalently bonded to an oxygen atom, it can form strong hydrogen bonds to each other molecules or dimethyl ether, because they lack a hydrogen atom attached to an electronegative atom, cannot form strong hydrogen bonds to each other

acid base reactions always favor the formation of a weaker acid and the weaker base. why?

because the outcome of an acid base rxn is determined by the position of an equilibrium . and equlibrium always favors the formation of the most stable (lowest potential energy) species. the weaker acid and the weaker base are more stable (less PE) than the stronger acid and base

However, when acidic ingredients are absent, the baking soda cannot be protonated, and CO2 is not produced. In such a situation, we must add

both the base (baking soda) and some acid

ETHENE AND PROPENE

c2h4 and c3h6 are among the most important industrial chemical sproduced in the US

Ethyl Alcohol (ethanol) Formula

c2h6o

alkyne examples

capillin: an antifungal agent dactylyne: a marine natural product that is an inhibitor of pentobarbital metabolism ethinyl estradiol: synthetic (lab made) alkyne whose estrogen-like properties have found use in oral contraceptives --> birth control!!!

ester

carbonyl group bonded to an alkoxyl (-OR) HAVE GENERAL FORMULA: RCO2R'E

protonation of a c=o

catalyzes a number of reactions For catalytic purposes, it is sufficient to have only a small percentage of the C=O bonds protonated.

entropy changes have to do with

changes in the relative order of a system

potential energy =

chemical energy

a factor (in addition to polarity and hydrogen bonding that affects the melting point of many organic compounds is the

compactness and rigidity of their individual molecules

alkyl halides

compounds in which a halogen atom (fluorine, chlorine, bromine, or iodine) replaces a hydrogen atom of an alkane ex. CH3Cl or CH3CH2Br also called haloalkanes classified as being primary, secondary, or tertiary

all lewis acids are

electrophiles that can accept an electron pair from a lewis base

the reaction that occurs in an aqueous solution of acetic acid is in

equilibrium

fats and oils contain ____ groups

ester

compounds containing a C=O bond directly next to an OH are generally mildly acidic, because

ex. acetic acids carboxylic acids

example of carboxylic acids

formic acid, acetic acid, and benzoic acid

Smaller alkanes (methane ch4 and butane c4h10) are

gases under ambient condition

alkyl groups

groups of atoms that are formed when one hydrogen atom is removed from an alkane molecule

cytosine hydrogen bonds with

guanine

mechanism for the reaction of water with hydrogen chloride

h20 + HCl --> h3o+ + Cl- a water molecule uses one of the nonbonding electron pairs of its oxygen to form a bond to a proton of HCl. this bond forms because the negatively charged electrons of the oxygen are attracted to the positively charged proton. The bond between hydrogen and chlorine breaks, and the electron pair goes to the chlorine atom this leads to the formation of a hydronium ion and chloride ion

a group of ethanol molecules is much ____ to separate from each other than a group of dimethyl ether molecules.

harder

nitriles

have carbon triple bonded nitrogen group with an R group the carbon and nitrogen are sp hybridized

heterolysis

heteroloysis of a bond to carbon atom can lead to either of two ions: an ion with a positive charge on the carbon atom called a carbocation or an ion with anegatively charged carbon atom called carbanion

molecules that are symmetrical generally have abnormally ____ MPs

high

primary carbon atom

if the carbon atom that bears the halogen is directly attached to only one other carbon

covalent bonds and potential energy

in covalent bonds, the lowest potential energy state occurs when atoms are at their ideal internuclear distance (bond length)

a convenient way to represent the relative PEs of molecules is

in terms of their relative ENTHALPIES (heat contents), H

electronegativity (for comparing atoms _____) and size (for comparing atoms in the same column)

in the same row (RIGHT LEFT)

Why are some alcohols soluble in water?

in these cases, the alkyl groups of the alcohols are relatively small (ex. ch3 in methanol) and the molecules therefore resemble water more than they do alkane. because carbon atoms combine with OH- to form hydrogen bonds with water.

proton acidity increases from left to right in a given row on the table due to

increasing stability of the conjugate base

carbanions

ion with negatively charged carbon atom electron rich anions that have unshared electron pair lewis bases seek a proton or some other positive center to which they can donate their electron pair and thereby neutralize their negative charge

carbocations

ion with positive charge on carbon electron deficient they have only six electrons in their 6 electrons in their valence shells and because of this carbocations are lewis acids short lived and highly reactive react rapidly with lewis bases (with molecules or ions tha tcan donate the electron pair that they need to achieve a stable octet of electrons electrophiles (electron loving)-- seek electrons

weak acids

ionize only slightly in aqueous solution

ethene

is is a natural plant hormone. produced naturally by fruits and is involved in the ripening process of these fruits

acetone

ketone that is found in blood, urine, and breath when diabetes mellitus is out of control

strong base

large pka value

the more potential energy an object has, the ____ stable it is

less

why is the proton bond strength weaker as we move down the column

less orbital overlap of successively larger elements down a column

many compounds of group IIIA elements like Boron and Aluminum are

lewis acids because group IIIA atoms have only a sextet of electrons in their outer shell

your body makes esters from

long-chain carboxylic acids called fatty acids by combining them with glycerol

the electrons of larger atoms like Iodine are

loosely held and easily polarized

fluorine

low polarizability small dispersion forces

a substance that boils at 150C at 1atm pressure will boil at a ____ temp if the pressur is reduced to .01 torr

lower

the formation of chemical bond is always associated with

lowering of PE of the atoms

alkyl group examples

methyl, ethyl, propyl, isopropyl , butyl, etc.

carboxylic acid

mildly acidic because their conjugate bases are resonance stabilized

conjugate base

molecule or ION that forms when an acid loses a proton

the primary source of alkanes are

natural gas and petroleum

if collectively , stronger bonds are formed in the products than in reactants, then change in H is

negative (EXOTHERMIC) Thus a negative change in H will contibute to making change in G negative and will consequently favor formation of products

Do alkanes have functional groups?

no

intermolecular (van der waals Forces)

not as strong as the forces in between ions but they do account for the fact that even completelyy nonpolar molecules can exist in liquids and solids ex. Dipole-dipole forces, hydrogen bonds, dispersion forces

when a lewis base seeks a positive center other than a proton, especially that of a carbon atom, chemists call it a

nucleophile (meaning nucleus loving)

ionic bond

occurs between two atoms with very large EN differences EX. LiF Formed when one or more electrons are transferred from one atom to another

1e10^-18

one debye (or one D)

way to name ethers

one way is to name the two alkyl groups attched to the oxygen in alphabetical order and add the word ETHER. If the two alkyl groups are the same, we use di- (ex. dimethyl ether)

Map of Electrostatic Potential (MEP)

one way to visualize the distribution of charge in a molec. regions of an electron density surface that has more negative are colored red. these regions would attrac positively charged species regions in a MEP that are less negative are blue and will attract electrons from another molecule

amines

organic compounds with an amino group considered an organic derivative of ammonia

Methane

principle component of natural gas ch4 the simplest alkane one major component of the early atmosphere still found in earth's atmosphere but not in an appreciable amount major component of Jupiter, Saturn, Uranus, and Neptune atmosphere some organisms produce methan from hydrogen and carbon dioxide (METHANOGENS)

leavening agents

produce CO2 that will make a dough or batter fluffy. A substance that triggers a chemical reaction that makes a baked product grow larger, or rise.

Because sodium bicarbonate is mildly basic, it will react with an acid to

produce carbonic acid, which in turn degrades into CO2 and water:

in lewis acid base theory

proton donors are not the only acids. many other species are acids as well i.e Aluminium chloride reacts with ammonia in the same way that a proton donor does.

higher molecular weight alkanes are obtained largely by

refining petroleum

release of heat

results from a change from PE to KE

constitutional isomers

same molecular formula, different connectivity

same molecular formula =

same molecular weight

if the carbon atom that bears the hydroxyl group also has two other carbon atoms attached to it, this carbon is called a __________, and the alcohol is a _______

secondary carbon, secondary alcohol

glucose contains

several hydroxyl groups (-oh) and in one of its forms contains an aldehyde group

weak acid

small pka value

baking soda is the household name for

sodium bicarbonate.

CARBON WITH A TRIPLE BOND IS ___ HYBRIDIZED

sp

in nitrile, carbon and nitrogen are ____ hybridized

sp

carbon with a double bond is ____ hybridized

sp2

A pair of electrons in an sp-hybridized orbital is held closer to the nucleus than a pair of electrons in an ___ or _____ hybridized orbital. As a result, electrons residing in an ____ orbital are stabilized by being close to the nucleus.

sp2 - or sp3 -hybridized orbital. sp

carbon with a single bond is ___ hybridzied

sp3

alkyl group

specific groups of carbon and hydrogen atoms that are not part of the functional groups groups that would be obtained by removing a hydrogen from an alkane An alkane with a hydrogen atom removed, e.g. CH3, C2H5; alkyl groups are often shown as 'R'. alkane's "functional group"

FROM THE STANDPOINT OF Covalent bonds, the state of greatest PE is the

state of free atoms, the state in which atoms are not bonded to each other at all. this is true bc the formation of chemical bond is always associated with lowering of PE of the atoms

weak acid = ____ conjugate base

strong

hcl

strong acid acid that is present in solution is really h3o+ because of leveling effect

large Ka means

strong acid if Ka is greater than 10, the acid will be completely dissociated from water

fluoride ion

strong base (because HF is weak acid)

Bronsted-Lowry acid

substance that can donate a proton proton donor

boiling point

temp at which the vapor pressure of a liquid equals the pressure of the atmosphere above it The temperature at which a liquid changes to a gas pressure dependent and reported to occur at 1atm nonpolar compounds (IMFs weak) usually have lower bps because they require less energy to separate molecules to transition from L--> G HEAVIER molecules requires greater thermal energy in order to acquire veloities great enough to escape Liquid phase and because the surface area of larger molecules acan be much greater, Intermolecular dispersion attractions can be also greater, further making it more difficult to separate IMF (Explains why increasing alkanes have increasing BPs)

if the carbon atom that bears the hydroxyl group also has 3 other carbon atoms attached to it, this carbon is called a __________, and the alcohol is a _______

tertiary carbon, tertiary alcohol

phenyl group

the benzene molecule minus one hydrogen atom

alkyl halides are classified as being primary, secondary, or tertiary. this classification is based on

the carbon atom to which the halogen is directly attached

the functional group of an alkyne

the carbon to carbon triple bond

acetone and acetaldehyde are examples of molecules with permanent dipoles because

the carbonyl groups that they contain is highly polarized

FUNCTIONAL GROUPS

the components of organic molecules that are most commonly involved in chemical reactions Defined groups of atoms in a molec. that give rise to the function (reactivity or physical properties) of the molec. often contain atoms having diff EN values and unshared electron pairs

percent ionization

the concentration of ionized acid in a solution divided by the initial concentration of acid multiplied by 100%

In order to compare acids without the use of pKa values, we must look at

the conjugate base of each acid

a drug's ability to transition between environments (polar and nonpolar) is a direct result of

the drug's acid-base properties

the strength of a bronsted lowry acid depends on

the extent to which a proton can be separated from it and transferred to a base removing the proton involves breaking a bond to the proton and it involves making the conjugate base more electrically negative

measure of strength for acids

the extent to which an acid transfers proton to a base

measure of strength for acids

the extent to which an acid transfers proton to a base percent of ionization

the energy required to overcome lattice energies and intermolecular or interionic attractions comes from

the formation of new attractive forces between solute and solventw

functional group of alcohol

the hydroxyl group attached to the sp3 hybridized carbon

because water is highly polar and because water is capable of forming strong hydrogen bonds,

the ion-dipole forces of attraction are also larger. the energy supplies by the formation of these forces i great enough to overcome the lattice energy and interionic attractions of an ionic crystal

the length of the arrow of the dipole moment indicates

the magnitude of the dipole moment

conjugate acid

the molecule or ion that forms when a base accepts a proton

in the process of dissolving

the molecules or ions must be separated from each other (like melting)

leveling effect

the observation that strong acids all have the same strength in water and are completely converted into solutions of H3O+ ions; strong bases are likewise leveled in water and are completely converted into solutions of OH- ions

in the liquid or solid state, dipole-dipole attractions cause the molecules to orient themselves so that

the positive end of one molec is directed toward the negative end of another

ionization

the process of adding or removing electrons from an atom or molecule, which gives the atom or molecule a net charge

two important factors determine the magnitude of dispersion forces:

the relative surface area of the molecule involved (generally longer molecules have greater attractive forces between them) the relative polarizability (how easily the electrons respond to a changing electric field) of electrons of the atoms involved

for the ionization of an acid, the less positive or more negative the value of the change in H is,

the stronger the acid will be because the more negative the change in H is, the more favorable it will be to make products from reactants during equilibrium. And if ionization results in a favor in product creation, the acid will be considered strong

the larger the pka of the conjugate acid

the stronger the base

bronsted lowry acid base reactions involve

the transfer of protons

the larger the pka value

the weaker the acid

the stronger the acid

the weaker the conjugate base

because HI, HBr, and HCl are all strong acids,

their conjugate bases (I-, Br-, Cl-) are all weak bases

ALDEHYDES AND KETONES have a ______ arrrangement of groups around the carbonyl carbon atom

trigonal planar arrangement thus the carbon atom is sp2 hybridyzed

t or f alcohols and phenols are different

true phenols differ significantly from alcohols in terms of their acidity

dipole moment formula

u= c * d c=electrostatic charge (typically on the order of 10^-10) and d= distance (typically on the order of 10^-8 cm) thus u is on the order of 10^-18

polar covalent bond

unequal sharing of electrons strongly influence the physical props and reactivity of molecules (because they usually are a part of all functional groups)

explanation for why nonpolar groups like long alkane chains avoid aqueous environments

very complex answer but really it is because of the unfavorable entropy change (from state to disorder to order) . for a nonpolar hydrocarbon chain to be accommodated by water, the water molecules have to form a more order structure around the chain and with this, the entropy change is unfavorable

Acetic acid is the main constituent in ____ solutions

vinegar

By determining the more stable conjugate base,

we can identify the stronger acid For example, if we determine that A- is more stable than B-, then HA must be a stronger acid than HB. we can identify the stronger acid

ammonia is a _____ base

weak

small Ka means

weak acid

water is a ____ acid

weak; pka = 15.7

equilibirum will always favor formation of the ___ acid

weaker acid (higher pka value)

phenyl group

when a benzene ring is attached to some other group of atoms in a molecule the benzene molecule minus one hydrogen atom

covalent bonds

when electrons are shared equally between atoms ex. ETHANE, METHANE, ETC. OCCURS BETWEEN TWO ATOMS WITH SIMILAR EN Bonds created by sharing electrons with other atoms.

why are alkynes more acidic that alkenes and alkanes

with hybrid orbitals, having more s charachter means that the electrons of the anions will usually be lower in energy and the anion will be more stable. (electrons of 2s orbitals have lower energy than those of 2p orbitals because electrons in 2s orbitals are much closer to the nucleus). thus the sp orbitals of the c-h bonds of ethyne are 50% s charachter while those of sp2 orbitals of ethene have 33.3% s this means in effect that the sp carbon atoms of ethyne act as if they were more electronegative than the sp2 carbon atoms of ethene

alcohols may be viewed structurally in two ways:

1. as hydroxyl derivatives of alkanes or 2. as alkyl derivates of water

alcohols general pka

15-18

alcohols usually have a pka of

15-18

____ alkyl groups can be derived from propane

2; propyl and isopropyl propyl: removal of a hydrogen from one of the end carbon atoms isopropyl: removal of a hydrogen from the middle carbon atom

alcohols

Alcohols are compounds that possess an O-H group, Alcohols can function very much like water (either as weak acids or as weak bases).

phenol

An alcohol with an aromatic ring; has slightly more acidic hydroxyl hydrogen's than other alcohols ex. Thymol ( a phenol found in thyme) and Estradiol (a sex hormone that contains both alcohols and phenols)

benzyl group

Bn- or Ph-CH2-

is hBr or hCl a stronger acid

Bromine and chlorine are in the same column of the periodic table (group 7A), so we must compare their size. Bromine is larger than chlorine and can better stabilize the negative charge that will be generated upon deprotonation. HBr is expected to be more acidic than HCl.

acetylene

C2H2

ethanol

C2H5OH

propylene

C3H6

Butane

C4H10

phenol

C6H5OH

acetic acid (ethanoic acid)

CH3COOH

dimethyl ether

CH3OCH3 or C2H6O (Same molecular formula as ethanol)

methanol

CH3OH

carboxyl group

COOH

is nh3 or ch4 more acidic

Carbon and nitrogen are in the same row of the periodic table, so we must compare their electronegativity values. nitrogen is more EN so it is better able to stabilize a negative charge that will be generated upon deprotonation. Therefore, NH3 is expected to be more acidic than CH4.

exothermic reactions

Chemical reactions that release a significant amount of heat. change in H (enthalpy ) is neg atoms have smaller enthalpy as products

Alkenes

CnH2n ,Hydrocarbons that contain double covalent bonds

ethyl alcohol

Ethanol/grain alcohol; Skin degermer and antiseptic, surfactant action, disinfect electrodes and face masks A primary alcohol

four factors that affect the stability of negative charges

Generally speaking, the order of priority is the order in which the factors were presented: 1. Atom. Which atom bears the charge? (How do the atoms compare in terms of electronegativity and size? Remember the difference between comparing atoms in the same row vs. atoms in the same column.) 2. Resonance. Are there any resonance effects that make one conjugate base more stable than the other? 3. Induction. Are there any inductive effects that stabilize one of the conjugate bases? 4. Orbital. In what orbital do we find the negative charge for each conjugate base? A helpful way to remember the order of these four factors is to take the first letter of each factor, giving the following mnemonic device: ARIO

sulfuric acid

H2SO4 (Strong Acid) a source of protons concentrated sulfuric acid is an aqueous mixture of h2so4 and h2o acid present in the solution is actually h3o+ because of the leveling effect. that is, h3o+ is a weaker acid than h2so4, so the protons are transferred from h2so4 to water, giving a high concentration of h3o+`

which one has a higher BP: HOCH2CH2CH2CH2OH CH3OCH2CH2CH2OH

HOCH2CH2CH2CH2OH

change in H

Heat of reaction measures the change in enthalpy of the atoms of the reactants as they are converted to products

teflon

One of the earlier plastic to be developed in 1938, a du pont trade name for the white, soft, waxy, and non-adhesive polymer of tetrafluoroethylene. very low polarizability of fluorine atoms make this compound have small dispersion forces and thus notoriously low bPs

inductive effects

The acidity of H-A increases with the presence of electron-withdrawing groups in A. electronic effects transmitted through BONDS. The inductive effect of a group can be electron donating or electron withdrawing. iNDUCTIVE EFFECT weakens as the distance from the group increases in the case of ethyl fluoride (ch3ch2F), the positive charge that the fluorine imparts to the carbon closest to is is greater than that imparted to C2

hydrogen bonds

Very weak bonds BUT very STRONG dipole-dipole attractions; occurs when a hydrogen atom in one molecule is attracted to the electrostatic atom in another molecule when hydrogen atoms bonds to a small, strongly electronegative atoms (O, N, and F) hydrogen bonds hold the base pairs of double-stranded DNA together

ACETIC ACID IS A

WEAK ACID

Why is water a great solvent?

Water's polarity allows it to chemically bond to many different types of compounds and/or molecules. positive ions i.e are surrounded by water molecules with the negative end of the water dipole point toward the positive ion

aspirin is an example of an acid that achieves biodistribution asa result of it's ability to lose a proton (acid). Explain.

consider the journey that aspirin takes after you ingest it. This journey begins in your stomach, where the pH can be as low as 2. Under these very acidic conditions, aspirin is mostly in its uncharged form. That is, there is very little of the conjugate base present. The uncharged form of aspirin is absorbed by the nonpolar environment of the gastric mucosa in your stomach and the intestinal mucosa in the intestinal tract. After passing through these nonpolar environments, the molecules of aspirin enter the blood, which is a polar (aqueous) environment with a pH of approximately 7.4. At that pH, aspirin exists mainly in the charged form (the conjugate base), and it is distributed throughout the circulatory system in this form. Then, in order to pass the blood-brain barrier, or a cell membrane, the molecules must be converted once again into the uncharged form so that they can pass through the necessary nonpolar environments. The drug is capable of successfully reaching the target because of its ability to exist in two different forms (charged and uncharged). This ability allows it to pass through polar environments as well as nonpolar environments.

carboxylic acids, esters, and amides all

contain a carbonyl group that is bonded to an oxygen or nitrogen atom

Alkanes

contains only a single bond CnH2n+2

as bond strength increases, acidity ______

decreases

bond strength to the proton

decreases as we move down the column of the periodic table, increasing its acidity

proton acidity increases as we descend a column in the periodic table due to

decreasing bond strength to the proton

If the pH of a solution is greater than the pka of a compound, the compound is likely to be

deprotonated

why does methane, a nonionic nonpolar substance become a liquid or solid at all

disperson (london) forces!

the relative acidities of ethyne, ethene, and ethane parallels the

effective electronegativity of the carbon atom in each compound (electronegativity of carbon in ethyne is greater than the carbon in both the ethene and ethane)

potential energy exists between objects that

either attract or repel each other

any _____ atom can act as a lewis acid

electron deficient