Acids and Bases

Question 1

Lewis Acid

Answer 1

Accepts pair of e-

Question 2

Lewis Base

Answer 2

Donates pair of e-

Question 3

Arrhenius Acid

Answer 3

Produces H+ in water

Question 4

Arrhenius Base

Answer 4

Produces OH- in water

Question 5

Bronstead-Lowry Acid

Answer 5

Donates H+

Question 6

Bronstead-Lowry Base

Answer 6

Accepts H+

Question 7

Acid Strenght

Answer 7

Weaker bond = more acidic

More polar = more acidic

Question 8

Strong Acids

Answer 8

HI, HBr, HCl, HNO3, HClO4, HClO3, H2SO4

Question 9

Strong Bases

Answer 9

NaOH, KOH, NH2-, H-, Ca(OH)2, Na2O, CaO

Question 10

Weak Acids

Answer 10

HF, HCN, CH2COOH (acetic acid), H20

Question 11

Weak Bases

Answer 11

NH3, NH4OH, C5H5N (pyridine), H20

Question 12

Hydrides as Acids/Bases

Answer 12

Basic to the left (Na+) and acidic to the right (H2S)
Metal hydrides basic or neutral
Non-metal hydrides acidic or neutral
Acidity increases down the period

Question 13

Conjugate acids and Conjugate bases

Answer 13

HA + H20 H3O+ (conj acid) + A- (conj base)
Strong acids have weak conj bases
weak acids have strong conj bases

Question 14

pH

Answer 14

pH=-log[H+]

Question 15

Amino acids/ organic acids

Answer 15

Amphoteric: act as acid or base dep on environment

weak CH3-CH3

Question 16

Autoionization of Water

Answer 16

Kw=[H3O+][OH-] Kw=10^-14

pKw= pH + pOH pH + pOH = 14

Question 17

Acid dissociation constant Ka

Answer 17

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

pKw= pKa + pKb = 14

Question 18

Equilibrium constant of conj base Kb

Answer 18

Kb=[OH-][HA]/[A-]

Question 19

pH Trends

Answer 19

larger Ka= smaller pKa = lower pH

Ka>1 or pKa

Question 20

Titration Neutralization

Answer 20

Acid + Base -> Water + Salt

Highly exothermic

Question 21

Equivalence Point

Answer 21

Mid point (almost verticle)
Equal equivalents of acid and base
Strong acid-weak base: equivalence above 7

Question 22

Half-equivalence point

Answer 22

point where 1/2 of acid has been neutralized by base
Most horizontal point
Equals pKa of weak acid
pH=pKa + log [H-]/[HA]

Question 23

Weak acid-weak base titration

Answer 23

pH range more compressed
acid>base pH below 7
acid

Question 24

Indicatiors

Answer 24

Weak acid whose conj base is a different color

pKa close as possible to pH of the titration’s equivalence point

Question 25

Polyprotic titrations

Answer 25

more than 1 equivalence and 1/2 equivalence pt

Question 26

Isoelectric pt

Answer 26

point where amino acid is neutral
pI=[pKa(1) + pKa(2)]/2
Uncharged amino acids have pI=6
Basic A.A: arginine, lysine, histidine (avg 1st two pKa for pI)
Acidic A.A: aspartic acid, glutamic acid (avg 2nd two pKa for pI)

Question 27

Salts

Answer 27

Compare conjugates of the salts to determine their acidic or basic contribution

Question 28

Buffer

Answer 28

Start with acid with pKa near pH of desired buffer range

Then mix equal amts of acid w/ its conjugate base