Intro

Question 1

if delta G = 0

Answer 1

you are at equilibrium

no work can be done

living systems are never at equilibrium

Question 2

foundation of biochem

Answer 2

all living things adhere to chemical + physical laws of the universe

Question 3

70% of living organisms is ___

Answer 3

water

Question 4

H2O unique properties

Answer 4

polar, h-bonding, acid/base

thermal regulation

Question 5

solvation in polar

Answer 5

1) break H-bonds & ionic bonds in NaCl
2) salt dissociates (inc. entropy)
3) make new H-bonds

delta H unchanged

Question 6

solvation in nonpolar

Answer 6

entropy decreased b/c H2O forms highly ordered structure

Question 7

amphipathic compounds

Answer 7

polar and nonpolar end

readily form ordered structures (ie. phospholipid bilayer)

inc. entropy of system by freeing up H2O

Question 8

pH equation

Answer 8

-log [H+]

Question 9

Ka equation

Answer 9

( [H+]x[A-]) / [HA]

Question 10

pKa equation

Answer 10

-log(Ka)

Question 11

stronger acids have…

Answer 11

high Ka

low pKa

Question 12

unlike pH, pKa is _____

Answer 12

constant

Question 13

pKa can be experimentally determined by …

Answer 13

titration

Question 14

at midpoint of titration curve…

Answer 14

pKa = pH

this is 0.5 OH- equiv, 1.5 etc..

Question 15

[HA] = [A-] at….

Answer 15

midpoint of titration curve

Question 16

if pH < pKa

Answer 16

HA dominates

Question 17

if pH > pKa

Answer 17

A- dominates

deprotonation

Question 18

weak acid buffering range is

Answer 18

+- 1 from pKa

Question 19

Henderson Hasselbach

Answer 19

pH = pKa + log( [A-] / [HA] )

Question 20

to use Henderson Hasselbach

Answer 20

find initial moles (multiply L by M)

divide by total volume (L)

plug in

Question 21

pKa can be used to tell you…

Answer 21

charge state of a molecule at a given pH

Question 22

pI

Answer 22

isoelectric point (on an even # of OH-… 1, 2, 3 etc)

pH when a molecule is neutral

to find, average pKas surrounding neutral state

Question 23

central dogma of molecular biology

Answer 23

info stored as DNA transcribed to RNA translated to protein