States Of Matter Gases And Liquids L-8 States of matter gases and liquids
→ \rightarrow → → \rightarrow → States of matter gases and liquids → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Recap
Numerical examples \text { Numerical examples } Numerical examples Real gases \text { Real gases } Real gases
Van der Waals equation \text { Van der Waals equation } Van der Waals equation Liquids { vapor pressure surface tension viscosity \text { Liquids } \left\{\begin{array}{l}\text {vapor pressure} \\ \text {surface tension} \\ \text {viscosity}\end{array}\right. Liquids ⎩ ⎨ ⎧ vapor pressure surface tension viscosity
→ \rightarrow → → \rightarrow → Recap → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Experimental evidence for real gases
States of matter gases and liquids → \rightarrow → → \rightarrow → Experimental evidence for real gases → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 P-V graph
Recap → \rightarrow → → \rightarrow → P-V graph → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Critical constants
P c − critical pressure P_c - \text {critical pressure} P c − critical pressure V c − critical volume V_c - \text {critical volume} V c − critical volume T c − critical temperature T_c - \text {critical temperature} T c − critical temperature
Experimental evidence for real gases → \rightarrow → → \rightarrow → Critical constants → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Continuity of liquid and gaseous states
Above T c T_c T c
Critical constants → \rightarrow → → \rightarrow → Continuity of liquid and gaseous states → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Compressibility factor
Z = p V n R T Z=\frac{pV}{nRT} Z = n RT p V Z = 1 (at all pressures) shows ideal gas behaviour which is shown by N 2 , O 2 , C O 2 , C H 4 N_2, O_2, CO_2, CH_4 N 2 , O 2 , C O 2 , C H 4
At low pressure all gases behave ideally
Temperature at which Z= 1 for different gases is called boyle's temperature
→ \rightarrow → → \rightarrow → Compressibility factor → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Boyle's temeprature
Temperature at which Z= 1 for different gases is called boyle's temperature
Continuity of liquid and gaseous states → \rightarrow → → \rightarrow → Boyle's temeprature → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Experimental observations
Found by Van der Waals (1873)
Pressure is lower than ideal
Volume of the molecules
P i d V i d = n R T P_{id} V_{id} = nRT P i d V i d = n RT
Compressibility factor → \rightarrow → → \rightarrow → Experimental observations → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Pressure correction
Pressure of the gas arises from collision with the walls
( n v ) × n v (\frac{n}{v})\times\frac{n}{v} ( v n ) × v n ( n v ) → (\frac{n}{v})\rightarrow ( v n ) → First term shows correction in size of the molecule
Second term shows correction in volume
P i d = ( p + ( n v ) 2 a ) P_{id} =(p+(\frac{n}{v})^2a) P i d = ( p + ( v n ) 2 a )
Boyle's temeprature → \rightarrow → → \rightarrow → Pressure correction → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Volume correction
V i d = ( V − n b ) V_{id} = (V - nb) V i d = ( V − nb ) P i d V i d = n R T P_{id} ~ V_{id} = nRT P i d V i d = n RT ( p + ( n v ) 2 a ) ( V − n b ) = n R T (p + (\frac{n}{v})^2a) (V - n b) = nRT ( p + ( v n ) 2 a ) ( V − nb ) = n RT Van der Waals equation
b- size of molecule
a- intermolecular force
Experimental observations → \rightarrow → → \rightarrow → Volume correction → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Volume correction
Substance \text {Substance} Substance a / b a r L 2 m o l − 1 a/bar L^2 mol^{-1} a / ba r L 2 m o l − 1 b / L m o l − 1 b/L mol^{-1} b / L m o l − 1
N 2 N_2 N 2 1.370 1.370 1.370 0.0387 0.0387 0.0387
O 2 O_2 O 2 1.382 1.382 1.382 0.0319 0.0319 0.0319
C O CO CO 1.472 1.472 1.472 0.0395 0.0395 0.0395
C O 2 CO_2 C O 2 3.658 3.658 3.658 0.0429 0.0429 0.0429
C H 4 CH_4 C H 4 2.303 2.303 2.303 0.0431 0.0431 0.0431
C 2 H 6 C_2 H_6 C 2 H 6 5.580 5.580 5.580 0.0651 0.0651 0.0651
Pressure correction → \rightarrow → → \rightarrow → Volume correction → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Vander waal's equation
( p + n 2 a v 2 ) ( v − n b ) = n R T \left(p+\frac{n^2 a}{v^2}\right)(v-n b)=n R T ( p + v 2 n 2 a ) ( v − nb ) = n RT
( p + ( n v ) 2 a ) ( v − n b ) = n R T \left(p+\left(\frac{n}{v}\right)^2 a\right)(v-n b)=n R T ( p + ( v n ) 2 a ) ( v − nb ) = n RT
p = n R T v − n b − ( n v ) 2 a p=\frac{n R T}{v-n b}-\left(\frac{n}{v}\right)^2 a p = v − nb n RT − ( v n ) 2 a
( p + n 2 a v 2 ) → cubic equation in V \left(p+\frac{n^2 a}{v^2}\right)\rightarrow\text {cubic equation in V} ( p + v 2 n 2 a ) → cubic equation in V
(a,b) different for different gases \text {(a,b) different for different gases} (a,b) different for different gases
Volume correction → \rightarrow → → \rightarrow → Vander waal's equation → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Things we have discussed
Boyle's law P ∝ 1 V P \propto \frac{1}{V} P ∝ V 1
Gay - Lussac's law V ∝ T / P ∝ T V \propto T/P \propto T V ∝ T / P ∝ T
Avogadro's hypothesis V ∝ n V \propto n V ∝ n
Kinetic molecular model
Ideal gas law
Real gases.
Volume correction → \rightarrow → → \rightarrow → Things we have discussed → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Vapour pressure
Vander waal's equation → \rightarrow → → \rightarrow → Vapour pressure → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Surface tension
Spherical shape of small liquid drops
Spheres - have the smallest surface area
Free surface energy
γ A = surface energy \gamma A = \text { surface energy } γ A = surface energy d ( γ A ) d A = γ + A d γ d A = 0 for liquids \frac{d(\gamma A)}{d A}=\gamma +\frac{A d\gamma}{dA} = 0 \text { for liquids } d A d ( γ A ) = γ + d A A d γ = 0 for liquids γ → N m γ → surface tension \gamma\rightarrow\frac{N}{m}\quad \gamma\rightarrow\text { surface tension } γ → m N γ → surface tension
Things we have discussed → \rightarrow → → \rightarrow → Surface tension → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Gasess law
Vapour pressure → \rightarrow → → \rightarrow → Gasess law → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Viscosity
Viscosity
f A ∝ d v d y \frac{f}{A}\propto \frac{dv}{dy} A f ∝ d y d v f A = η d v d y \frac{f}{A}=\eta \frac{d v}{d y} A f = η d y d v η → viscosity (poise) \eta\rightarrow\text {viscosity (poise)} η → viscosity (poise)
Surface tension → \rightarrow → → \rightarrow → Viscosity → \rightarrow → → \rightarrow →
States Of Matter Gases And Liquids L-8 Thank you
Gasess law → \rightarrow → → \rightarrow → Thank you → \rightarrow → → \rightarrow →
Resume presentation
States Of Matter Gases And Liquids L-8 States of matter gases and liquids $\rightarrow$ $\rightarrow$ States of matter gases and liquids $\rightarrow$ Recap $\rightarrow$ Experimental evidence for real gases
