CHM 2046C
Sample Module 13 Name: ___Answers_____
Part A. Laws of
Thermodynamic 10 points
1. Describe the
difference between Thermodynamics and Kinetics of a chemical reaction.
All systems eventually reach equilibrium;
the spontaneous movement toward equilibrium is
determined by thermodynamic properties of the system.
Thermodynamics deals
with the introversions of heat and other forms of energy and allow us to
predict the direction and extent of chemical reactions and other spontaneous
processes.
The speed at which the system moves toward
its final state is determined by the kinetic properties of the
system. Even though a reaction is spontaneous
and is driven toward equilibrium, it may not get there very quickly.
The dispersal of energy and the dispersal
of matter are the two driving forces for chemical
reactions and physical processes. For every spontaneous reaction,
one of these driving forces (or both) must operate.
The dispersal of energy
is the most important driving force at lower temperatures whereas the
dispersal of matter is the more important driving force at
higher temperatures. If both matter and energy are dispersed,
the reaction is spontaneous. If only one of the two is
dispersed, then the spontaneity depends upon the relative magnitude of the two
and the temperature. If neither is dispersed, then the reaction cannot be
spontaneous. Disorder is created by the dispersal
of both.
3. What
do you understand by the word “entropy”?
The word entropy is usually interpreted as “disorder”.
Entropy is defined as the amount of molecular randomness in a thermodynamic
system.
4. State
the First Law of Thermodynamics.
The total internal energy of an isolated
system is constant.
5. State
the Second Law of Thermodynamics.
In any spontaneous process, the total
entropy of a system and its surroundings always increases.
6. State
the Third Law of Thermodynamics.
The entropy of a perfectly ordered
crystalline substance at Zero Kelvin (0 K) is Zero.