BCH441 - CH 3 EXAM QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS VERIFIED
what is thermodynamics?
-branch of science that studies the effects of changes in temp, pressure, and volume on
physical systems at the macroscopic scale by analyzing the collective motion of their
particles using statistics
why would you want to study the thermodynamics of biological systems?
-understand how chemical energy is converted into life
-by studying systems under diff conditions, we can measure basic physical and
chemical properties without knowing the details
system
-portion of the universe with which we are concerned
-the surroundings=everything else
-isolates system - nothing in or out
-closed system - energy exchange
-open system - enregy and or matter exchange
first law
-total eneergy of an isolated system is conserved
-E is the internal energy - translational, vibrational, rotational energy of molecules,
chemocal bonding and nonbonding interactions between molecules. can be modified by
chemical processes
, -e keeps track of heat transfer and work expenditure in the system
-e is independent of path (state function)
dE=q+w
-change in energy=heat in/out+work done on/by system
-if limited to mechanical work, then dE=q-PdV
-if no change in volume occurs, dE=q
-at constant pressure, dE is not always = q
1 joule
.239 cal
1 cal
4.184 joule
biological processes at constant pressure
H=E+PV
-H=enthalpy
-internal energy of a system pluss the product of its volume and the external pressure
van't hoff plot
-enthalpy change, H, can be determined by slope of a plot of RlnKeq vs 1/T
-deltaH(1/T)=-RlnKeq
second law
-systems tend toward disorder and randomness
-systems tend to proceed from ordered to disordered states
-all processes proceed towards equilibrium (minimum potential energy)
entropy
COMPLETE SOLUTIONS VERIFIED
what is thermodynamics?
-branch of science that studies the effects of changes in temp, pressure, and volume on
physical systems at the macroscopic scale by analyzing the collective motion of their
particles using statistics
why would you want to study the thermodynamics of biological systems?
-understand how chemical energy is converted into life
-by studying systems under diff conditions, we can measure basic physical and
chemical properties without knowing the details
system
-portion of the universe with which we are concerned
-the surroundings=everything else
-isolates system - nothing in or out
-closed system - energy exchange
-open system - enregy and or matter exchange
first law
-total eneergy of an isolated system is conserved
-E is the internal energy - translational, vibrational, rotational energy of molecules,
chemocal bonding and nonbonding interactions between molecules. can be modified by
chemical processes
, -e keeps track of heat transfer and work expenditure in the system
-e is independent of path (state function)
dE=q+w
-change in energy=heat in/out+work done on/by system
-if limited to mechanical work, then dE=q-PdV
-if no change in volume occurs, dE=q
-at constant pressure, dE is not always = q
1 joule
.239 cal
1 cal
4.184 joule
biological processes at constant pressure
H=E+PV
-H=enthalpy
-internal energy of a system pluss the product of its volume and the external pressure
van't hoff plot
-enthalpy change, H, can be determined by slope of a plot of RlnKeq vs 1/T
-deltaH(1/T)=-RlnKeq
second law
-systems tend toward disorder and randomness
-systems tend to proceed from ordered to disordered states
-all processes proceed towards equilibrium (minimum potential energy)
entropy
