Chapter 3: Biochem Basics

Question 1

What are the two forms of energy in chemistry?

Answer 1

1. Kinetic energy
2. Potential energy

Question 2

What is the equation for Gibbs free energy?

Answer 2

Delta G = delta H - T delta S (T represents temp & H represents enthalpy)

Question 3

What is the equation for enthalpy?

Answer 3

Delta H = delta E + PdeltaV (E represents the bond energy of products in the system & P is pressure, & V is volume)

Question 4

Delta G increases when delta H _________ & decreasing with increasing entropy

Answer 4

Increases

Question 5

Delta G is spontaneous when its ________ & nonspontaneous when its __________

Answer 5

Negative, positive

Question 6

The value of delta G depends on the _____________ of the reactants & products

Answer 6

concentration

Question 7

What is the equation for delta G related to equilibrium constant

Answer 7

delta G = -RT lnKeq

Question 8

If we wanted to calculate the delta G for a reaction in the body what is the equation?

Answer 8

delta G = delta G prime + RT ln Q (Q uses the actual concentration of the products & reactants not the equilibriums)

Question 9

All reactions proceed through a ___________________ that is unstable & takes a lot of energy to produce

Answer 9

transition state (TS

Question 10

The __________________ is the energy required to produce the transition state

Answer 10

Activation energy (Ea)

Question 11

A catalyst lowers the Ea of a reaction ___________ changing the delta G

Answer 11

Without

Question 12

Oxidation is a ________ of electrons & Reductions are a _______ of electrons

Answer 12

Loss, Gain

Question 13

How do you recognize oxidation reactions?

Answer 13

1. Gain of oxygen atoms
2. Loss of hydrogen atoms
3. Loss of electrons

Question 14

How do you recognize reduction reactions?

Answer 14

1. Loss of oxygen atoms
2. Gain of hydrogen atoms
3. Gain of electrons

Question 15

What is the Bronsted -Lowry definition of acids & bases?

Answer 15

Acids are proton (H+) donor & bases are proton (H+) acceptors

Question 16

What is the lewis acid & base definition?

Answer 16

Acids are electron-pair acceptors & bases are electron pair donors

Question 17

The larger the Ka value the _____________ the acid & the smaller the Ka value the ____________ the acid

Answer 17

Stronger, weaker

Question 18

The lager the Kb value the __________ the base and the smaller the Kb the _________ the base

Answer 18

Stronger, weaker

Question 19

Amphoteric substances

Answer 19

Substances that can act as a base & acid

Question 20

The acid with the lower pKa is the __________ acid & the base with the lower pKb is the ___________ base

Answer 20

Stronger

Question 21

Buffer

Answer 21

Is a solution that resist changing pH when small amount of acid or base is added

Question 22

The buffer system for our blood plasma is the ____________

Answer 22

Bicarbonate system

Question 23

Gibbs free energy is the amount of energy in a reaction available to do ___________ work

Answer 23

Chemical

Question 24

If delta G equal 0 means what

Answer 24

Its at equilibrium

Question 25

_________ is the study of how quickly a reaction occurs but its does not determine whether or not a reaction will occur

Answer 25

Kinetics

Question 26

A __________ lowers the energy of the transition state, which decreases the Ea and increases the amount of product formed per unit of time

Answer 26

catalyst

Question 27

When a reaction is favorable (or spontaneous) means it will occur in the ___________ direction

Answer 27

Forward

Question 28

When a reaction is unfavorable (or nonspontaneous) means it will occur in the ___________ direction

Answer 28

Reverse

Question 29

In a reaction if there is a compound that has been oxidized or reduce then it means its a __________ pair

Answer 29

redox

Question 30

When an molecule is in its standard state (ex. O2) its oxidation state is __________ but when its in a compound its oxidation will be positive or negative

Answer 30

zero

Question 31

When dealing with the Bicarbonate buffer system when you hold your breath what happens?

Answer 31

When you hold your breath the CO2 concentration in your blood increase which will increase H2CO3 (carbonic acid) which will decrease the pH

Question 32

Kinetic energy comes from __________ of molecules

Answer 32

Movement

Question 33

Potential energy comes from energy stored in _________ bonds

Answer 33

Chemmical

Question 34

1st law of thermodynamics

Answer 34

States that the energy of the universe is constant (when energy of the system decrease the energy of the surroundings increase)

Question 35

2nd law of thermodynamics

Answer 35

States that the disorder (entropy) of the universe tends to increase (spontaneous reactants tend to increase the disorder of the universe)

Question 36

Favorable reactions have a _________ delta G

Answer 36

Negative

Question 37

Reactions with a negative delta G are _____________ & reactions with a positive delta G are ________

Answer 37

Exergonic (energy leaves the system), endergonic (energy is added)

Question 38

The sign of thermodynamic quantities depends on the point of view of the _________

Answer 38

System (not the surroundings)

Question 39

A negative delta G means that the system will go to a _________ free energy state ( & a system always moves in the direction of the lowest free energy )

Answer 39

Lower

Question 40

A ____________ Keq means that more products are present at equilibrium & equilibrium tends to move toward the lowest energy state so when Keq is ______ products have lower free energy than reactants

Answer 40

Large

Question 41

_____ is irrelevant to free energy of products & reactants only Keq is

Answer 41

Q

Question 42

At equilibrium how is Q related to Keq?

Answer 42

Its equal (Q=Keq) so forward reaction rate = reverse reaction rate & the net concentrations of reactants & products don't change

Question 43

When delta G = 0 what does it mean for the reaction

Answer 43

Its at equilibrium so it occurs at the same rate for the forward & reverse reactions

Question 44

Enzymes only have a kinetic role not a thermodynamic so it will only affect the ______ not concentration of products & reactants

Answer 44

rate

Question 45

When oxidation occurs so does a ___________ reaction an

Answer 45

Reduction (redox pair)

Question 46

What is the bicarbonate buffer system

Answer 46

1. H2CO3 ----------> H+ CO3 2. CO2 +H2O -----> H2CO3

Question 47

A positive delta S means what?

Answer 47

Increase in disorder

Question 48

A negative delta S means what?

Answer 48

An increase in order (but entropy is favorable when its an increase in disorder)

Question 49

When delta G is negative but delta H is positive what can that tell you?

Answer 49

That its working against the reaction since a positive delta H means an input of energy but a negative delta G means its spontaneous & happens on its own

Question 50

A more negative delta G means what?

Answer 50

An increase in spontaniety

Question 51

A negative delta H means what & a positive delta H means what>?

Answer 51

Positive means its endothermic (input of energy due to bonds forming) & negative means it's exothermic (energy released due to bonds breaking which would increase the disorder (positive delta S)

Question 52

1st law of thermodynamics

Answer 52

The energy of the universe is constant (where energy of the system decrease the energy of the surroundings increase)

Question 53

2nd law of thermodynamics

Answer 53

The entropy tends to increase

Question 54

The value of delta G depends on _______________ of reactants & products

Answer 54

Concentrations

Question 55

_____ is the concentration at any point & k is the concentration at equilibrium

Answer 55

Q

Question 56

Even though a reaction may be spontaneous it will be slow due to what?

Answer 56

A large activation energy

Question 57

When one atom is reduced another must be __________

Answer 57

Oxidized (redox pair)

Question 58

Any anion or any neutral species with a lone pair of electrons can function as a _______

Answer 58

Base

Question 59

Hassel Balch equation

Answer 59

pH= pka + log [A-]/[HA]