thermodynamics

Question 1

energy must be conserved.. but..

Answer 1

can take different forms

Question 2

entropy

Answer 2

a measure of a systems disorder and tends to increase

Question 3

what is free energy change determined by

Answer 3

the change in enthalpy and entropy

Question 4

free energy must be negative…

Answer 4

for a reaction to be spontaneous

Question 5

what are: open systems that constantly exchanged matter and energy with their surroundings

Answer 5

organisms

Question 6

what do enzymes do

Answer 6

increase the rates of thermodynamically favourable reactions

Question 7

the universe can be divided into two sections

Answer 7

system

everything else

Question 8

system

Answer 8

what can be controlled

Question 9

everything else

Answer 9

the surroundings

Question 10

closed system

Answer 10

only allows energy and work

Question 11

isolated systems

Answer 11

no transfer of matter, energy or work across boundary

Question 12

open systems

Answer 12

transfer of matter, energy and work across the boundary

Question 13

we usually use..

Answer 13

closed system, where only work and energy can cross the boundary

Question 14

whether a reaction absorb or releases hat cannot predict…

Answer 14

whether the reaction will happen or not, therefore we must look to entropy

Question 15

first law of thermodynamics

Answer 15

‘energy can neither be created or destroyed’
-the change in the internal energy of a closed thermodynamic system is equal to the sum of work done on the system and the amount of heat energy supplied to the system.

Question 16

the change in the internal energy of a closed thermodynamic system is equal to..

Answer 16

the sum of work done on the system and the amount of heat energy supplied to the system

Question 17

most spontaneous reactions…

Answer 17

release internal energy

Question 18

when a system undergoes change: but these into an equation: deltaU= Q-W

Answer 18

u= internal energy of the system; Q=heat put into the system, W= work done ; delta= indicates change

deltaU= Q-W
or
deltaU=U(final)- U(initial)

Question 19

second law of thermodynamics

Answer 19

the total entropy of any isolated thermodynamic system tends to increase over time

Question 20

entropy basics

Answer 20

• measure of disorder of a system
• the ‘ordileness’ of a system is related to how likely an arrangement is to happen by chancr–> the more ways this could happen by chance- the greater the disorder

Question 21

the higher the entropy

Answer 21

the more disordered

Question 22

part of the second law is the..

Answer 22

law of statistics- with enough molecules- stats become inevitable

Question 23

deltaG

Answer 23

gibbs free energy

Question 24

gibbs free energy

Answer 24

combines both the change in entropy in a closed system, and the disorder added to the environment by the hear into a single function

Question 25

gibbs equation

Answer 25

deltaG=deltaH-TdeltaS

Question 26

to be spontaneous a reaction deltaG must be..

Answer 26

negative or equal to zero

Question 27

how com life is well ordered and operates a long way from equilibrium

Answer 27

due to coupled reactions

Question 28

how do coupled reactions make life more ordered and predictable

Answer 28

extremely favourable reactions are coupled (free energy is much smaller than zero) with extremely unfavourable reactions (free energy is more than 0)
-relies on the reverse of the unfavourable reaction being very slow in the cell

Question 29

example of where cells maintains pools of accessible, favourable reactions that can be used to drive other reactions

Answer 29

eg. the hydrolysis of ATP= -31jKmol-1