Thermodynamics

Question 1

what is glycolysis?

Answer 1

process where glucose converted to pyruvate
aerobic process

Question 2

what do we need to understand for thermodynamics?

Answer 2

why do biochemical processes go the way they of and stop where they do

life obeys laws of thermodynamics

Question 3

what are the two sections in thermodynamics?

Answer 3

the system (easily measured and controlled)
the universe (everything else)

Question 4

what is a closed boundary?

Answer 4

where only work and energy can cross the boundary into the system
no crossing of physical matter

Question 5

what is the first law of thermodynamics?

Answer 5

energy can neither be created or destroyed

Question 6

explain the first law of thermodynamics

Answer 6

energy (U) change of system defined as difference between heat (Q) absorbed by system from surroundings and work (W) done by system on the surroundings

chaining an energy from one state to another

Question 7

what is the equation for when the system undergoes change?

Answer 7

deltaU = Q-W

u= internal energy of the system
q= heat put into the system
w= work done by the system on the surroundings

delta indicates change

Question 8

what is meant by the term work?

Answer 8

force times the distance moved
- motion

Question 9

what are the different forms of work?

Answer 9

gravitational force exerted by one mass on another
expansional force exerted by a gas
tensional force of a muscle fibre
electrical force of charge

Question 10

what is the enthalpy equation?

Answer 10

H = U + PV

h= enthalpy
u = internal energy
p = pressure
v= volume

Question 11

how is enthalpy equivalent to heat?

Answer 11

volume changes in most biological reactions are insignificant
difference between internal energy and enthalpy negligible

energy change = enthalpy change

Question 12

is spontaneity necessary?

Answer 12

2 objects that are brought together
heat spontaneously flows from hot to cold

additional element spontenaity needed

Question 13

can you predict a reaction direction?

Answer 13

is reaction absorbs or releases heat cannot predict whether reaction will happen

no

Question 14

what is the second law of thermodynamics?

Answer 14

the total entropy of any isolated thermodynamic system tends to increase over time, approaching maximum value

Question 15

isolated system

Answer 15

allows no transfer of matter, energy to work across the boundary

Question 16

what is entropy?

Answer 16

measure of the disorder in the system

Question 17

explain entropy

Answer 17

orderliness of system related to how likely arrangement is likely to happen by chance

more ways in which can happen by chance, greater the disorder

law of statistics, not absolutes

Question 18

how do you calculate entropy?

Answer 18

s = kb in w

s= entropy
kb= Boltzmann constant5
w= number of ways

Question 19

what is Gibbs free energy?

Answer 19

energy provided to environment as heat will create further disorder in environment

Question 20

what is the free energy equation?

Answer 20

G = H -TS

g= free energy
h= enthalpy
t= temperature
s= entropy

JMol-1

G less than or = 0 means spontaneous

Question 21

what are coupled reactions?

Answer 21

achieved by coupling extremely favourable reactions to unfavourable reactions

relies of reverse of the unfavourable reaction being slow in cell

Question 22

living systems take in organised energy

Answer 22

high enthalpy, low entropy

Question 23

turning this into disorderly heat energy and waste products

Answer 23

low enthalpy, high entropy

Question 24

what are the standard conditions?

Answer 24

25oC
1 atm
pH 7