Chem II Exam 3

BAAD meaning

Bases accept, acids donate

[H3O][OH]=kw=

1 × 10^-14

An amphoteric species can be

an acid or a base

Brønsted-Lowry bases accept ? and Brønsted-Lowry acids donate ?

protons

pH for H+ formula

-logH+

pOH for OH- formula

-logOH-

pH + pOH=

14

Higher Ka value means

stronger acid

Lower Ka value means

weaker acid

Does a high Ka have a lower or higher pH?

lower

A buffer forms when a

conjugate weak acid/weak base pair are mixed together.

Formula to calculate pH

pH=pKa+log[base]/[acid]

Spontaneous process

A negative ΔS indicates that the system has become

more ordered

ΔS formula

nΔS products-ΔS reactants

If both ΔH and ΔS are positive, then T must be

large

Entropy is positive when

the degrees of freedom of the system increases

G formula

G= H-TS

If a chemical reaction has a negative ∆H and a negative ∆S, then

it will be spontaneous at low temperatures and non-spontaneous at high temperatures.

A reaction which is endothermic and has an overall increase in entropy is

spontaneous only at high T

If a chemical reaction has a positive ∆H and a negative ∆S, then

it will be non-spontaneous at all temperatures.

A reaction will be spontaneous at all temperatures if

∆H is negative and ∆S is positive

salt of a weak base and a strong acid have what type of pH

acidic

salt of a weak acid and a strong base have what type of pH

basic

larger kb means

stronger base

smaller kb means

weaker base

amphoteric

capable of acting as an acid or base depending on what they are reacting with

amphiprotic

substance that can accept and donate hydrogen ions