S_05

Question 1

Arrhenius acid

Answer 1

substance that produces H+ ions in aqueous solution

Question 2

Arrhenius base

Answer 2

Substance that OH- ions in aqueous solution

Question 3

Bronstead-Lowry acid

Answer 3

Proton (H+) donor

Question 4

Bronstead-Lowry base

Answer 4

Proton (H+) acceptor

Question 5

Bronstead-Lowry
Acid/base conjugate pairs are related by?

Answer 5

The gain or loss of a proton (H+)

Question 6

Lewis acid

Answer 6

Electron pair acceptor

Question 7

Lewis base

Answer 7

Electron pair donor

Question 8

Autoionization of water - H2O is amphoteric

Answer 8

Can behave as either an acid or a base

Question 9

If acid is added to pure water: (K
w) =

Answer 9

1.0 x 10-14 at 25 oC, always)

Question 10

If base is added to pure water: (K
w) =

Answer 10

= 1.0 x 10-14 at 25 oC, always)

Question 11

pH=

Answer 11

= -log[H3O+]
[H3O+] = 10^(-pH)

Question 12

pOH=

Answer 12

= -log[OH-]
[OH-] = 10^(pOH)

Question 13

pH + pOH = ?

Answer 13

14

Question 14

Strong acids and bases (ionize?, Kb?)

Answer 14

Ionize completely in water; Don’t have a Ka value in data sheet

Question 15

Weak acids

Answer 15

Don’t ionize completely in water; Have a Ka
value in data sheet)

Question 16

pKa =

Answer 16

= -log Ka

Question 17

Weak bases

Answer 17

Don’t ionize completely in water; Have a Kb
value in data sheet

Question 18

Degree of ionization

Answer 18

% of acid (or base) that exists as ions

Question 19

Mixtures of weak acids

Answer 19

Only the acid with the largest Ka value will contribute an appreciable [H+]. H+ ions produced by this acid will prevent weaker acid from ionizing (Le Chatelier’s Principle)

Question 20

The more negative the anion…

Answer 20

…the more difficult to release a proton (H+) (The higher the potential energy of the anion)

Question 21

What are binary acids

Answer 21

Compounds made of δ+ H atom(s) and atom(s) of one other element:
Posses highly polarized (and weaker) H-Y bond
When H-Y bond breaks, it release a H+
Acidity increases with increasing stability of the conjugate base

Question 22

Determining factor of acidity

Answer 22

Size of atom holding negative charge in conjugate base
Size of ions increases down a group
Larger atoms disperse the negative charge over a larger volume

Question 23

Stronger acid = (3)

Answer 23

-lower charge density (lower P.E)
-More stable conjugate base
-Easier to form (easier to break H-Y bond)

Question 24

Weakest bond (H-I) =

Answer 24

easier to break = stronger acid

Question 25

Smallest anion =

Answer 25

least stable = HF weakest acid

Question 26

The larger the attraction for electrons…

Answer 26

…the better the atom stabilize the neg. charge

Question 27

What are oxyacids

Answer 27

Made of a nonmetal atom hat covalently bonds one or more oxygen atom. One or more of these oxygen atoms is covalently bonded to one H atom

Question 28

What happens to the polarization and strength of an O-H bond the more the electronegativity of the atom

Answer 28

The bond is polarized and weakened

Question 29

Increasing the electronegativity of atom binding the O atom increases what

Answer 29

acidity

Question 30

What are oxides

Answer 30

Compounds made of an element (metal or non-metal) and oxygen atoms

Question 31

Covalent oxides dissolve and react with water to form what from acidic solutions

Answer 31

Oxyacids

Question 32

Ionic oxides posses what

Answer 32

Very basic O2- ions

Question 33

Kw = ?

Answer 33

Ka x Kb

Question 34

Buffer

Answer 34

Solution that resists to change in pH when an acid or a base is added

Question 35

[H3O+]= (in buffer solution)

Answer 35

KaCa/Cb

Question 36

pH in a buffer solution =?

Answer 36

pH=pka+log10(cb/ca)

Question 37

If Cb = Ca pH=?

Answer 37

pH=pKa

Question 38

PH of an effective buffer =

Answer 38

pka +- 1

Question 39

A buffer neutralizes any added H+ or OH- keeping [H3O+] and [OH-] almost cnst

Answer 39

Usually H3O+ is added to reactants + OH-

Question 40

nb = ?

Answer 40

nb = cb x v

Question 41

Buffer capacity =?

Answer 41

Amount of acid or base the solution can successfully buffer

Question 42

Titration =?

Answer 42

Determination of the amount (not the concentration) of one substance by addition of a measured amount of a second substance

Question 43

Analyte =?

Answer 43

Substance whose concentration is being determined

Question 44

Titrant

Answer 44

Substance of known concentration added to react with the analyte

Question 45

Rapide change in pH is used to calculate what

Answer 45

the equivalence point