GAS LAWS.ppt quarter 4 module 1 powerpoint

science

1. I. Physical
Properties
Gas LawsGas Laws

2. A. Kinetic Molecular TheoryA. Kinetic Molecular Theory
Particles in an ideal gas…
•have no volume.
•have elastic collisions.
•are in constant, random, straight-
line motion.
•don’t attract or repel each other.
•have an avg. KE directly related to
Kelvin temperature.

3. C. Characteristics of GasesC. Characteristics of Gases
Gases expand to fill any container.
•random motion, no attraction
Gases are fluids (like liquids).
•no attraction
Gases have very low densities.
•no volume = lots of empty space

4. C. Characteristics of GasesC. Characteristics of Gases
Gases can be compressed.
•no volume = lots of empty space
Gases undergo diffusion & effusion.
•random motion

5. D. TemperatureD. Temperature
ºF
ºC
K
-459 32 212
-273 0 100
0 273 373
 32FC
9
5
 K = ºC + 273
Always use absolute temperature
(Kelvin) when working with gases.

6. E. PressureE. Pressure
area
force
pressure
Which shoes create the most pressure?

7. E. PressureE. Pressure
Barometer
•measures atmospheric pressure
Mercury Barometer
Aneroid Barometer

8. E. PressureE. Pressure
Manometer
•measures contained gas pressure
U-tube Manometer Bourdon-tube gauge

9. E. PressureE. Pressure
2
m
N
kPa
KEY UNITS AT SEA LEVEL
101.325 kPa (kilopascal)
1 atm
760 mm Hg
760 torr
14.7 psi

10. F. STPF. STP
Standard Temperature & PressureStandard Temperature & Pressure
0°C 273 K
1 atm 101.325 kPa
-OR-
STP

11. II. The Gas
Laws
BOYLES
CHARLES
GAY-
LUSSAC
Gas LawsGas Laws

12. A. Boyle’s LawA. Boyle’s Law
P
V
PV = k

13. A. Boyle’s LawA. Boyle’s Law
The pressure and volume of
a gas are inversely related
•at constant mass & temp
P
V
PV = k

14. k
T
V

V
T
B. Charles’ LawB. Charles’ Law

15. k
T
V

V
T
B. Charles’ LawB. Charles’ Law
The volume and absolute
temperature (K) of a gas are directly
related
•at constant mass & pressure

16. k
T
P

P
T
C. Gay-Lussac’s LawC. Gay-Lussac’s Law

17. k
T
P

P
T
C. Gay-Lussac’s LawC. Gay-Lussac’s Law
The pressure and absolute
temperature (K) of a gas are directly
related
•at constant mass & volume

18. = k
PV
T
D. Combined Gas LawD. Combined Gas Law
P
1V
1
T
1
=
P
2V
2
T
2
P
1V
1T
2 =
P
2V
2T
1

19. GIVEN:
V
1 = 473 cm
3
T
1 = 36°C = 309K
V
2 = ?
T
2 = 94°C = 367K
WORK:
P
1V
1T
2 = P
2V
2T
1
E. Gas Law ProblemsE. Gas Law Problems
A gas occupies 473 cm
3
at 36°C.
Find its volume at 94°C.
CHARLES’ LAW
TV
(473 cm
3
)(367 K)=V
2(309 K)
V
2
= 562 cm
3

20. GIVEN:
V
1 = 100. mL
P
1 = 150. kPa
V
2 = ?
P
2 = 200. kPa
WORK:
P
1V
1T
2 = P
2V
2T
1
E. Gas Law ProblemsE. Gas Law Problems
A gas occupies 100. mL at 150.
kPa. Find its volume at 200. kPa.
BOYLE’S LAW
PV
(150.kPa)(100.mL)=(200.kPa)V
2
V
2 = 75.0 mL

21. GIVEN:
V
1
= 7.84 cm
3
P
1
= 71.8 kPa
T
1
= 25°C = 298 K
V
2
= ?
P
2
= 101.325 kPa
T
2
= 273 K
WORK:
P
1
V
1
T
2
= P
2
V
2
T
1
(71.8 kPa)(7.84 cm
3
)(273 K)
=(101.325 kPa)
V
2 (298 K)
V
2 = 5.09 cm
3
E. Gas Law ProblemsE. Gas Law Problems
A gas occupies 7.84 cm
3
at 71.8 kPa &
25°C. Find its volume at STP.
P T V
COMBINED GAS LAW