Lec1 :
Temperatureoslps
Young and Freeman 17 .
1-2)
·
Diff in
temp- transfer in energy
in a known
way
·
any physical property that changes with temperature " can be used to measure temperature
↳ thermometer utilises this
physical property to measure
temperature
↳
freezing pt .
+
boiling pt of water
. are two fixed points
·
Kelvin scale is independent of properties of any particular material
Constant-Volume Gas Thermometer : all
extrapolated plots reach same
temperature
↳ slide 7
"Temperature"
·
tic) and T(k)
·
+ (k) =
+(c) + 273 15.
·
plots of pressure as a function of T (slide 7)
close to Kelvin scale
this thermometer
employing
·
comes
=
, State Variables
·
physical quantities that describe
physical state of system
a e .
g
container of gas
·
examples
-
temperature -
mass
pressure energy
-
-
-
volume
values of state variables change when "disturbance" in
system
·
can a occurs
·
once it has ended variables will stop changing and become constant in time
:
THERMAL EQUILIBRIUM reached
↳ state variables have
single value=> same
everywhere in system
Thermal
Equilibrium ① look at slide 10 on
"properties of thermal
equilibrium"
(bodies)
↳ I systems don't have to be in direct thermal
contact if each is indiv. connected to 3rd system
=> ZEROTH Law of
Thermodynamics
, Determining number of moles of a substance
·
Sample of CO2 .
It has a mass of 90g
.
How
many
moles in substance ?
Mtotal
n =
Mmolar
n
=Oa2 gmol =
2 04.
mols
(N)
x = n .
NA
=
(2 04 mol) (6 022x1823)
.
.
=
, Summary
Temperature : -
builds
upon subjective concepts of hotness and coldness
-
makes measurements objective
scale
physics Kelvin
=>
in is
=> T(k) = t (0) + 273 15 .
chamber (constant)
interact leg -temperature
vacuum
not
does surrounding
with
is same everywhere
throughout system ( other variables ?
+
state variables constant when isolated thermal
equilibrium
system is in
·
Geg Tip same at each point throughout
system
·
two systems only in thermal
equilibrium if both have same temperature I
if
using Length
of metal rod as thermom .
=> I will also be est at T E
.
(p,
etc. )
Zeroth law of
Thermodynamics :
two bodies thermal thermal
>
-
in
equilibrium with third body are also in
equilibrium with each
other
Temperatureoslps
Young and Freeman 17 .
1-2)
·
Diff in
temp- transfer in energy
in a known
way
·
any physical property that changes with temperature " can be used to measure temperature
↳ thermometer utilises this
physical property to measure
temperature
↳
freezing pt .
+
boiling pt of water
. are two fixed points
·
Kelvin scale is independent of properties of any particular material
Constant-Volume Gas Thermometer : all
extrapolated plots reach same
temperature
↳ slide 7
"Temperature"
·
tic) and T(k)
·
+ (k) =
+(c) + 273 15.
·
plots of pressure as a function of T (slide 7)
close to Kelvin scale
this thermometer
employing
·
comes
=
, State Variables
·
physical quantities that describe
physical state of system
a e .
g
container of gas
·
examples
-
temperature -
mass
pressure energy
-
-
-
volume
values of state variables change when "disturbance" in
system
·
can a occurs
·
once it has ended variables will stop changing and become constant in time
:
THERMAL EQUILIBRIUM reached
↳ state variables have
single value=> same
everywhere in system
Thermal
Equilibrium ① look at slide 10 on
"properties of thermal
equilibrium"
(bodies)
↳ I systems don't have to be in direct thermal
contact if each is indiv. connected to 3rd system
=> ZEROTH Law of
Thermodynamics
, Determining number of moles of a substance
·
Sample of CO2 .
It has a mass of 90g
.
How
many
moles in substance ?
Mtotal
n =
Mmolar
n
=Oa2 gmol =
2 04.
mols
(N)
x = n .
NA
=
(2 04 mol) (6 022x1823)
.
.
=
, Summary
Temperature : -
builds
upon subjective concepts of hotness and coldness
-
makes measurements objective
scale
physics Kelvin
=>
in is
=> T(k) = t (0) + 273 15 .
chamber (constant)
interact leg -temperature
vacuum
not
does surrounding
with
is same everywhere
throughout system ( other variables ?
+
state variables constant when isolated thermal
equilibrium
system is in
·
Geg Tip same at each point throughout
system
·
two systems only in thermal
equilibrium if both have same temperature I
if
using Length
of metal rod as thermom .
=> I will also be est at T E
.
(p,
etc. )
Zeroth law of
Thermodynamics :
two bodies thermal thermal
>
-
in
equilibrium with third body are also in
equilibrium with each
other
