Q4-W1: Entropy and Gibbs Free Energy Flashcards
- process which
can take place by itself
SPONTANEOUS
process
which can neither take place by
itself nor by initiation
NON-SPONTANEOUS
Flow of water up a hill
NON-SPONTY
Dissolution of salt in water
SPONTY
Evaporation of water in an open
vessel
SPONTY
Flow of water down the hill
SPONTY
Dissolution of sand in water
NON-SPONTY
Spontaneous reactions are (___________) reactions; they take place immediately (______________________________.)
SELF-DRIVEN, WITHOUT ANY ASSISTANCE FROM EXTERNAL SOURCE
tossing a coin in the air and it
drops on the ground
SPONTY
falling of water in a waterfall
SPONTY
SPONTY IS _____ DIRECTION ONLY.
ONE
A lump of sugar
spontaneously dissolves
in a cup of coffee, but
dissolved sugar does not
spontaneously reappear
in its original form.
SPONTY
Water freezes
spontaneously below
0°C, and ice melts
spontaneously above
0°C (at 1 atm).
SPONTY
Heat flows from a
hotter object to a colder
one, but the reverse
never happens
spontaneously.
SPONTY
A piece of sodium metal
reacts violently with
water to form sodium
hydroxide and hydrogen
gas. However, hydrogen
gas does not react with
sodium hydroxide to
form water and sodium.
SPONTY
Iron exposed to water
and oxygen forms rust,
but rust does not
spontaneously change
back to iron.
SPONTY
Spontaneity in chemical
reactions is ALSO ____________________
UNDIRECTIONAL
It gives an idea about the direction of energy or heat flow.
Second Law of Thermodynamics
Second Law of Thermodynamics?
that as energy is transferred or transformed, more and more of it is wasted.
As per this law heat flows from
hotter to colder bodies or you
can say that energy flows from
higher level to lower level.
Second Law of Thermodynamics
”The state of entropy of the
entire universe, as an isolated
system, will always ____________
over time.”
INCREASE
degree of randomness
and disorder
ENTROPY
measure of freedom of
the molecules
ENTROPY
entropy in phases of matter:
They have
no freedom at all
that means they
have least entropy.?
SOLID
entropy in phases of matter:
They have
more freedom than
they have in ice. That
means entropy of
water is more than ice.?
LIQUID
Entropy in phases of matter:
They are most
free and therefore
out of all phases of
water, steam has the
highest entropy.
GAS
Qualitative entropy rules:
Entropy ______________ when the
number of molecules increase
during a reaction.
INCREASES
Qualitative entropy rules:
Entropy ___________ with an
increase in temperature.
INCREASES
Qualitative entropy rules:
Entropy ____________ when a gas
forms from either a liquid or
solid.
INCREASES
Entropy ____________ when a liquid
forms from a solid.
INCREASES
Entropy _______________ when a liquid
forms from a solid.
INCREASES
Entropy is a thermodynamic
quantity that is a ____________________________________________________ among the different
possible ways that system can
contain energy. SI unit is J/K
measure of how
spread out or dispersed the energy
of a system is
ENTROPY CHANGE:
SOLID TO LIQUID
MELTING
LIQUID TO GAS/VAPOR
VAPORIZATION
SOLUTE TO SOLUTION
DISSOLVING
If the reaction produces more
gas molecules than it consumes,
∆S is ______________
POSITIVE
If the total number of gas
molecules diminishes, ∆S is _________
NEGATIVE
Decrease in pressure of the
system, ∆S is
POSITIVE
Decrease in number of molecules
and gases are converted to
solids, ∆�� is
NEGATIVE
When solid is converted to two
gaseous products, ∆�� is
POSITIVE
If there is no net change in the
total number of gas molecules,
∆�� may be positive or
negative, but will be relatively
small numerically.
TRUE
Energy available to do useful
work. Used to express the
spontaneity of a reaction more
directly. SI unit is kJ.
Gibbs Free Energy
A thermodynamic quantity used
to describe heat changes taking
place at constant pressure. SI
unit is J.
ENTHALPY
A thermodynamic quantity that is a
measure of how spread out or
dispersed the energy of a system is
among the different possible ways
that system can contain energy. SI
unit is J/K.
ENTROPY
