Chem
Acids/Bases
● Henderson-Hasselbach: 𝑝𝐻 = 𝑝𝐾𝑎 + 𝑙𝑜𝑔([𝑐𝑜𝑛𝑗𝑢𝑔𝑎𝑡𝑒 𝑏𝑎𝑠𝑒]/[𝑎𝑐𝑖𝑑])
○ Indicators change colors at half-equivalence points, where [conjugate
base]=[acid]
■ [Indicator]=[conjugate base]
○ At midpoint, pH=pKa
○ pKa = 14 - pKb
(𝑝𝐻−𝑝𝐾𝑎)
○ To find ratio of base: acid, do 10
○ Lowest pKa = more readily deprotonated
23
● Avogadro: 6.022 * 10 = 1 mol
○ Number of particles in 1 mol
○ Faraday constant = charge of 1mol electrons = 965000C/mol
● Molarity: mol/L
● Molality: mol/kg
● Dilution: 𝑀1𝑉1 = 𝑀2𝑉2
● Gas constant (R): 8.3 J/molK
○ Or 0.08 Latm/molK
● To get starting mass from moles and molar mass,
○ Take the mol of electrons TRANSFERRED (1-electrons measured) * molar mass
● Bronsted-Lowry acid is proton donor
○ BL acid = weak acid
○ Bronsted-Lowry base is proton acceptor
○ Bronsted-Lowry rxn makes salt + water
● Lewis acid accepts electron pair
○ Lewis base donates electron pair (lone pair of electrons)
○ Lewis acids have empty orbitals
● Lewis AND Bronsted acids
○ H2O, CH3CH2CO2H, CH3C=N
● Arrhenius
○ Acids are hydronium donors
○ Bases hydroxide donors
● Strong Acids
○ HI
○ HBr
○ HCl
○ HCl4 (perchloric)
○ H2SO4
○ HNO3
● Strong Bases
○ NaOH
○ KOH
, ○ LiOH
○ Ba(OH)2
○ Sr(OH)2
● Buffer made from weak acid/base with conjugate base/acid
○ 1 acid 1 base
○ Resist changes in pH when small volumes of strong acids/bases are added
● Solubility
○ All salts of Group 1 metals and nitrate are water soluble
𝑛 𝑛
○ 𝐾𝑠𝑝 = [𝑥] [𝑥]
■ X is the individual elements’ equilibrium concentrations, n is number of
them in equilibrium equation (coefficient)
■ Do not include solids in Ksp
● Protons more acidic if adjacent to EN groups
○ Carbonyl very EN and makes nearby protons acidic
● Cl = more acidic
● Acidity least → most: cyclohexanol < hexanol < phenol
● Acetone, keto form predominates
○ Low boiling point
○ Polar aprotic
○ Cannot participate in H bonding
● Diols protect aldehydes and ketones
○ Diols preferentially react with aldehyde because of decreased steric hindrance
○ Diol = glycerol + 1 fatty acid
● Reactive side chains protected to prevent unwanted side products
● Phenol group
○ Ortho- means on adjacent C
○ Meta- means separated by 1 C
○ Para- means on opposite sides of ring
● Primary alcohol + PCC → aldehyde
○ Alcohol boiling point increased by H bonding
● Primary alcohol + acyl halide → ester
○ Primary alcohol + alcohol → ester
● Ketone
○ Carbonyl + 2 R groups
○ Higher temperature with strong base favors more stable form
○ Ketone + strong base = aldol condensation
■ Aldol enolate is nucleophile
■ Retro-aldol enolate is leaving group
● Jones reagent (CrO3, H2SO4, acetone) oxidizes alcohol → ketone or aldehyde on
aromatic rings
○ Non-specific
○ Needs acidic, aqueous environment
○ Aldehyde is carbonyl + H + 1 R group
○ Strong oxidizing agent
, ○ Can convert aldehyde → carboxylic acid
● Fructose is ketose sugar unable to tautomerize to other sugars
● 2-Butanol + PCC = ketone
○ Secondary alcohol
● Tertiary alcohol cannot be oxidized
○ No H bound to carbon with OH
○ It cannot be bc it would break C-C bond
○ So tertiary alcohol cannot make a ketone
● Hemiketal bound to OR group, OH group, and 2 R groups
○ Ketone and alcohol needed for synthesis
● Amine attacks carbonyl carbon to form imine
○ Primary amines are H bond donors and acceptors
○ Reacts to form a peptide bond, but the amide group is the actual peptide bond
● Hemiacetal from cyclization of carbonyl and hydroxyl (on glucose)
● Breaking disulfide bond = reduction = oxidation occurs
○ Makes a ring
○ Can only break disulfide bond via reducing agent
● Common Reduction Rxns
○ Ketone/aldehyde → carboxyl is reduction
■ KNOW THIS ONE
○ If you see an alcohol in product, = reduction
■ Alcohols are always product of reduction
○ O2 → H2O is reduction
● Neutralization rxn: acid + base → water + salt
● Chelation: molecule binds to metal ion
● Combustion: fuel + oxidizing agent → heat
● Closer electronegative group is to OH, more electronegative, more acidic, lower pKa
● Polar solvents H bond
○ Can only H bond if H bound to highly EN atom (O, F, N)
○ ONLY polar solvents
● More double bonds means more susceptible to peroxidation
● Covalent bonds, no dipole
○ Coordinate covalent bonds between metal cation and lewis base
● ALL molecules exhibit London dispersion forces
● Electron affinity decreases w Zeff decrease
● NADH is reduced form of NAD
○ Acts as reducing agent, becomes oxidized
● LiAlH4 (Lithium aluminum anhydride) strong reducing agent
● Decanoic acid = soap because long hydrocarbon chain
● Aqueous Acid/Base
○ Stronger acids = weaker conjugate bases
■ But stronger acids = more stable conjugate bases
○ Conjugate acids and bases differ by 1 proton
○ Hydroxides formed with group I metals
, −14
○ 𝐾 * 𝐾 = 𝐾 where 𝐾 = 10
𝑎 𝑤 𝑤
𝑏
■ Kw and pH inverse relationship
■ Kw and temp have proportional relationship
○ Autoionization: rxn between same substance’s molecules to produce ions
○ pH decreased by adding H3O+ ions
■ Increased by adding OH- ions
■ pH of an integer: n*10^-m log becomes m-0.n
● Ex: 1.8*10^-5 → 5-0.18 → 4.82
𝑠𝑝 [ ]
○ Solubility product: 𝐾 = 𝑝𝑟𝑜𝑑𝑢𝑐𝑡 [𝑝𝑟𝑜𝑑𝑢𝑐𝑡 ]
1 2
■ If Q > Ksp, precipitation happens
● So if Ksp equation is > Ksp, something forms (ex: kidney stones)
■ And if Q < Ksp, no precipitation
○ Saturated → unsaturated increases fluidity
■ Cannot pack as closely
■ More unsaturated if cold
■ Saturated = single bonds only = cis
● Saturated also means solute is present at maximum concentration
■ Unsaturated = double bonds = trans
● Unsaturated also means solute is below maximum concentration
● If more solid is added than the solvent can handle, it dissolves
until point of saturation
■ More double bonds = lower melting point
● So unsaturated lower melting point than saturated
○ Phenol → hydroxyquinone needs 2 oxidation steps
■ 1: phenol → quinone
■ 2: quinone → hydroxyquinone
■ Phenol + oxidizing agent = quinone
■ Ubiquinone is CoQ
Elution
● Eluted fastest if pI < pH
○ pI = pH, neutral and will not bind to negative
○ pI > pH, amino acid +, binds to negative, inhibits elution
○ pI between pKa1 and pKa2
○ If pH > pKa, take a proton away
● Titration with acid lowers pH
○ Strong acid and weak base, inflection point < pH 7
○ Weak acid and strong base, inflection point > pH 7
● Titration indicator pKa should be near pH at equivalence pt
● Lower net positive charge eluted at lower pH
○ Higher positive charge eluted at higher pH
● Substrate binding
Acids/Bases
● Henderson-Hasselbach: 𝑝𝐻 = 𝑝𝐾𝑎 + 𝑙𝑜𝑔([𝑐𝑜𝑛𝑗𝑢𝑔𝑎𝑡𝑒 𝑏𝑎𝑠𝑒]/[𝑎𝑐𝑖𝑑])
○ Indicators change colors at half-equivalence points, where [conjugate
base]=[acid]
■ [Indicator]=[conjugate base]
○ At midpoint, pH=pKa
○ pKa = 14 - pKb
(𝑝𝐻−𝑝𝐾𝑎)
○ To find ratio of base: acid, do 10
○ Lowest pKa = more readily deprotonated
23
● Avogadro: 6.022 * 10 = 1 mol
○ Number of particles in 1 mol
○ Faraday constant = charge of 1mol electrons = 965000C/mol
● Molarity: mol/L
● Molality: mol/kg
● Dilution: 𝑀1𝑉1 = 𝑀2𝑉2
● Gas constant (R): 8.3 J/molK
○ Or 0.08 Latm/molK
● To get starting mass from moles and molar mass,
○ Take the mol of electrons TRANSFERRED (1-electrons measured) * molar mass
● Bronsted-Lowry acid is proton donor
○ BL acid = weak acid
○ Bronsted-Lowry base is proton acceptor
○ Bronsted-Lowry rxn makes salt + water
● Lewis acid accepts electron pair
○ Lewis base donates electron pair (lone pair of electrons)
○ Lewis acids have empty orbitals
● Lewis AND Bronsted acids
○ H2O, CH3CH2CO2H, CH3C=N
● Arrhenius
○ Acids are hydronium donors
○ Bases hydroxide donors
● Strong Acids
○ HI
○ HBr
○ HCl
○ HCl4 (perchloric)
○ H2SO4
○ HNO3
● Strong Bases
○ NaOH
○ KOH
, ○ LiOH
○ Ba(OH)2
○ Sr(OH)2
● Buffer made from weak acid/base with conjugate base/acid
○ 1 acid 1 base
○ Resist changes in pH when small volumes of strong acids/bases are added
● Solubility
○ All salts of Group 1 metals and nitrate are water soluble
𝑛 𝑛
○ 𝐾𝑠𝑝 = [𝑥] [𝑥]
■ X is the individual elements’ equilibrium concentrations, n is number of
them in equilibrium equation (coefficient)
■ Do not include solids in Ksp
● Protons more acidic if adjacent to EN groups
○ Carbonyl very EN and makes nearby protons acidic
● Cl = more acidic
● Acidity least → most: cyclohexanol < hexanol < phenol
● Acetone, keto form predominates
○ Low boiling point
○ Polar aprotic
○ Cannot participate in H bonding
● Diols protect aldehydes and ketones
○ Diols preferentially react with aldehyde because of decreased steric hindrance
○ Diol = glycerol + 1 fatty acid
● Reactive side chains protected to prevent unwanted side products
● Phenol group
○ Ortho- means on adjacent C
○ Meta- means separated by 1 C
○ Para- means on opposite sides of ring
● Primary alcohol + PCC → aldehyde
○ Alcohol boiling point increased by H bonding
● Primary alcohol + acyl halide → ester
○ Primary alcohol + alcohol → ester
● Ketone
○ Carbonyl + 2 R groups
○ Higher temperature with strong base favors more stable form
○ Ketone + strong base = aldol condensation
■ Aldol enolate is nucleophile
■ Retro-aldol enolate is leaving group
● Jones reagent (CrO3, H2SO4, acetone) oxidizes alcohol → ketone or aldehyde on
aromatic rings
○ Non-specific
○ Needs acidic, aqueous environment
○ Aldehyde is carbonyl + H + 1 R group
○ Strong oxidizing agent
, ○ Can convert aldehyde → carboxylic acid
● Fructose is ketose sugar unable to tautomerize to other sugars
● 2-Butanol + PCC = ketone
○ Secondary alcohol
● Tertiary alcohol cannot be oxidized
○ No H bound to carbon with OH
○ It cannot be bc it would break C-C bond
○ So tertiary alcohol cannot make a ketone
● Hemiketal bound to OR group, OH group, and 2 R groups
○ Ketone and alcohol needed for synthesis
● Amine attacks carbonyl carbon to form imine
○ Primary amines are H bond donors and acceptors
○ Reacts to form a peptide bond, but the amide group is the actual peptide bond
● Hemiacetal from cyclization of carbonyl and hydroxyl (on glucose)
● Breaking disulfide bond = reduction = oxidation occurs
○ Makes a ring
○ Can only break disulfide bond via reducing agent
● Common Reduction Rxns
○ Ketone/aldehyde → carboxyl is reduction
■ KNOW THIS ONE
○ If you see an alcohol in product, = reduction
■ Alcohols are always product of reduction
○ O2 → H2O is reduction
● Neutralization rxn: acid + base → water + salt
● Chelation: molecule binds to metal ion
● Combustion: fuel + oxidizing agent → heat
● Closer electronegative group is to OH, more electronegative, more acidic, lower pKa
● Polar solvents H bond
○ Can only H bond if H bound to highly EN atom (O, F, N)
○ ONLY polar solvents
● More double bonds means more susceptible to peroxidation
● Covalent bonds, no dipole
○ Coordinate covalent bonds between metal cation and lewis base
● ALL molecules exhibit London dispersion forces
● Electron affinity decreases w Zeff decrease
● NADH is reduced form of NAD
○ Acts as reducing agent, becomes oxidized
● LiAlH4 (Lithium aluminum anhydride) strong reducing agent
● Decanoic acid = soap because long hydrocarbon chain
● Aqueous Acid/Base
○ Stronger acids = weaker conjugate bases
■ But stronger acids = more stable conjugate bases
○ Conjugate acids and bases differ by 1 proton
○ Hydroxides formed with group I metals
, −14
○ 𝐾 * 𝐾 = 𝐾 where 𝐾 = 10
𝑎 𝑤 𝑤
𝑏
■ Kw and pH inverse relationship
■ Kw and temp have proportional relationship
○ Autoionization: rxn between same substance’s molecules to produce ions
○ pH decreased by adding H3O+ ions
■ Increased by adding OH- ions
■ pH of an integer: n*10^-m log becomes m-0.n
● Ex: 1.8*10^-5 → 5-0.18 → 4.82
𝑠𝑝 [ ]
○ Solubility product: 𝐾 = 𝑝𝑟𝑜𝑑𝑢𝑐𝑡 [𝑝𝑟𝑜𝑑𝑢𝑐𝑡 ]
1 2
■ If Q > Ksp, precipitation happens
● So if Ksp equation is > Ksp, something forms (ex: kidney stones)
■ And if Q < Ksp, no precipitation
○ Saturated → unsaturated increases fluidity
■ Cannot pack as closely
■ More unsaturated if cold
■ Saturated = single bonds only = cis
● Saturated also means solute is present at maximum concentration
■ Unsaturated = double bonds = trans
● Unsaturated also means solute is below maximum concentration
● If more solid is added than the solvent can handle, it dissolves
until point of saturation
■ More double bonds = lower melting point
● So unsaturated lower melting point than saturated
○ Phenol → hydroxyquinone needs 2 oxidation steps
■ 1: phenol → quinone
■ 2: quinone → hydroxyquinone
■ Phenol + oxidizing agent = quinone
■ Ubiquinone is CoQ
Elution
● Eluted fastest if pI < pH
○ pI = pH, neutral and will not bind to negative
○ pI > pH, amino acid +, binds to negative, inhibits elution
○ pI between pKa1 and pKa2
○ If pH > pKa, take a proton away
● Titration with acid lowers pH
○ Strong acid and weak base, inflection point < pH 7
○ Weak acid and strong base, inflection point > pH 7
● Titration indicator pKa should be near pH at equivalence pt
● Lower net positive charge eluted at lower pH
○ Higher positive charge eluted at higher pH
● Substrate binding
