Chapter 23 Flashcards
What is a spontaneous change?
Change that occurs without input of energy from outside the system
What is a non spontaneous change?
Change that occurs only if the surroundings continuously supply energy to the system
What happens to a reaction when a spontaneous process has begun?
no further energy is needed
If a change in one direction is spontaneous, what will it be in the reverse direction?
nonspontaneous
Within the first law of thermodynamics, what is energy?
It is conserved, neither created or destroyed. it was rather transferred in the form of heat and work
What does the law of conservation of energy apply to? What does it not predict?
it applies to all changes, but it does not allow us to predict the direction of a spontaneous change
What is the total energy of the universe constant?
Esys = -Esurr
Esys + Esurr = Euniv = 0
What do spontaneous exothermic processes include?
-freezing and condensation at low temperatures,
-combustion reactions,
-oxidation of iron and other metals
What does a spontaneous endothermic process include?
melting and vaporization at higher temperatures,
dissolving of most soluble salts.
What does the sign of delta H not predict itself?
direction of a spontaneous change
What are all spontaneous endothermic process resulted in?
an increase in the freedom of motion of the particles in system; also exhibit an increase in entropy
What is the key factor affecting the direction of a spontaneous process?
A change in the freedom of motion of particles
What does it mean to be quantized?
a system of particles also has different allowed energy states
What is a micro state?
It is a state that is present in each quantized energy state for a system of particles. at a given set condition they are the same total energy as any other
the larger the number of possible micro states, the larger the number of?
ways a system can disperse its energy
A system with fewer micro states has?
lower entropy
A system with more micro states has?
higher entropy
What is a reversible process?
one that occurs in such tiny increments that the system remains at equilibrium, and the direction of the change can be reversed by an infinitesimal reversal of conditions
When we consider both system and surroundings, what is found out?
all real processes occur spontaneously in the direction that increases the entropy of the universe.
For a process to be spontaneous:
a decrease in the entropy of the system must be offset by a larger increase in the entropy of the surroundings.
Which has a zero point, entropy or enthalpy?
entropy
What factors affect entropy?
-temperature (increases as temperature increase)
-entropy depends on the physical state of the substance (increases from solid liquid to gas)
-the formation of a solution affects entropy
-entropy is relaxed to atomic size and molecular complexity
true or false: S is higher or larger atoms for molecules of the same type
true
How does S pertain in alltropes?
it is higher in the form that allows the atoms more freedom of motion, but it only hold true for substances in the same physical state
