Test on KMT, Gases, liquids
? degrees C = 155 K
-118 degrees C
A flashbulb of volume .0056 L contains Oxygen gas, O_2, at a pressure of 536.9 kPa and a temperature of 36.0 degrees C. How many moles of Oxygen gas does the flashbulb contain?
.0012 moles
A gas has a pressure of 380 torr at a temperature of 50.0 degrees C. The volume of the gas is 800.0 mL, How many moles of gas are present?
.015 mol
? L = 125.0 mL
.1250 L
? L = 654 cm^3
.654 L
What is the volume of the gas sample that occupies .650 L at 4.0 degrees Celsius and 85.5 kPa when the temperature is increased to 50.0 degrees Celsius?
.758 L
Calculate the volume in liters of 0.588 g NH_3(g) at STP.
.773 L
? mol = 96.8 g SO_3(g)
1.21 moles SO_3(g)
What is the volume occupied by 3.50 g Cl_2(g) at 45.0 degrees C and 99.3 kPa?
1.31 L
? atm = 1050 torr
1.38 atm
A sample of CO_2(g) occupies a volume of 64.0 cm^3 at 130 degrees Celsius and 0.372 atm. What is pressure of the gas if volume is reduced to 12.0 cm^3 at constant temperature?
1.98 atm
? g CH_3OH = .320 mol CH_3OH
10.3 g CH_3OH
? Pa = 1 atm
101,325
? torr = 150 kPa
1130 torr
A sample of gas has a pressure of 354.6 kPa at 5.00 degrees C and occupies a volume of 1.60 L. What pressure will the gas have if the temperature is raised to 35.0 degrees Celsius and its volume changes to 0.50 L?
1257 kPa
? psi = 1 atm
14.7
A sample of gas has a pressure of 4.50 atm at 15.0 degrees C and can occupy a volume of 26.0 L. What pressure will the gas exert if its temperature is changed to 45.0 degrees C, and it's volume is changed to 0.80 L?
16.1 atm
What would the final temperature of a gas have to be in order to keep the pressure constant at 25.0 degrees C its volume decreased from 27.0 L to 15.0 L?
166 K
? kPa = 1279 mmHg
170.5 kPa
Determine the total pressure of a gas mixture that containes CO_2 at a partial pressure of 745 torr, NO_2 at a partial pressure of .800 atm, NO at a partial pressure of 94.6 kPa.
2.71 atm PT
A spray can is used until it is empty, except for the propellant gas, which has a pressure of 1.1 atm at 23.0 degrees C. If the can is thrown into a fire (T = 475 degrees C) what will be the pressure in the hot can?
2.8 atm
What is the pressure exerted by 3.00 moles of a gas trapped in a 3.5 mL container at 25.0 degrees Celsius?
21 atm (2100 kPa)
A sample of gaseous ammonia is found to occupy 250 mL under laboratory conditions of 27.0 degrees C and 94.6 kPa. What volume would it occupy at STP?
210 mL
? mL = .235 L
235 mL
A sample of gas occupies 26.5 L at 25 degrees C and 745 mm Hg. What would its volume be if the pressre increased to 785 mm Hg with the temperature staying constant?
25.1 L
? kPa = 2.55 atm
258 kPa
A sample of gas at 2525 kPa has a temperature of 285 K. If the volume is held constant what would the pressure be if the temperature changed to 303 K?
2680 kPa
A sample of Carbon dioxide gas occupies 300.0 mL at 10.0 degrees C and 750 torr. What volume will the gas have at 30.0 degrees C and 885 torr?
272 mL
What are K and atm at STP?
273 K; 1 atm
? in. Hg = 1 atm
29.92
? K = 25 degrees C
298 K
A gas mixture containing oxygen, nitrogen, and carbon dioxide has a total pressure of 32.9 kPa. If PO_2 = 6.6 kPa and PN_23.0 kPa, what is PCO_2?
3.3 kPa
1.5 moles of oxygen gas exerts a pressure of .500 atm when contained in a volume of .8500 L. What must be the temperature of the gas?
3.5 K
? mole H_2O = 68.0 g H_2O
3.77 moles H_2O
Two moles of a gas exert a pressure of 1520 torr at a temperature of 127 degrees C. What volume does the gas occupy under these conditions?
30 L
? L O_2 = 1.50 mole O_2
33.6 L O_2
? K = 75.0 degrees Celsius
348 K
65.0 g of sulfur dioxide gas occupies a volume of 4.50 L at 25 degrees C. WHat is the pressure exerted by this gas
5.5 atm (560 kPa)
? torr = 555 mm Hg
555 torr
A gas occupies a volume of 2.5 L at 35 degrees Celsius and contains .650 moles. What pressure does the gas exert?
6.6 atm
5.00 L container is filled with Nitrogen gas to a pressure of 3.00 atm at 250 degrees Celsius. What volume container would be needed to store this same gas at STP?
7.83 L
The total pressure exerted by a mixture of CO_2 and O_2 gas is 726.5 torr. What is the partial pressure of the oxygen if the pressure exerted by CO_2 is 25.8 torr?
700.7 torr
? cm^3 = 75 mL
75 cm^3
? mm Hg = 1 atm
760
? torr = 1 atm
760
5.00 L of a gas exerts a pressure of 765 mm Hg at 26.0 degrees Celsius. What would be its pressure at 70.0 degrees Celsius?
878 mm Hg
Determine the total pressure of a gas mixture that ocntains oxygen, nitrogen, and helium. The partial pressures are PO_2 = 20.0 kPa; PN_2 = 46.7 kPa; PHe = 26.7 kPa
93.4 kPa
What is the Kinetic Molecular Theory
A simple model for gases under many conditions
When the volume of a gas and its frequency are held constant, if the temperature decreases then the pressure of the gas must decrease. Explain.
As Temperature decreases, kinetic energy decreases, because particles move slower, particles will reach the walls less often, and fewer collisions mean less pressure
When the temperature and the number of moles of gas in a sample is held constant and the volume is decreased what will happen to the pressure? Explain using kinetic molecular theory.
As Volume decreases, the particles travel a shorter distance to the container walls, so moving particles reach the walls more often resulting in more collisions, so Pressure increases
When 1 mole of a gas is contained in 2 liters of volume at 25 degrees Celsius it exerts a pressure of 760 mm Hg. When temperature is raised to 50 degrees Celsius why does the pressure increase?
As temperature increases, the KE of the particles increases, the particles move faster, they reach the walls of the container more often, more collisions, more pressure
Which gas will effuse faster, CO or NO_2? How much faster?
CO effuses 1.282 times faster than NO_2
Atmospheric Pressure
Decreases with altitude increase; average pressure at sea level
What is "kinetic energy"?
Energy associated with the motion of an object
Arogabro's Law?
If pressure and temperature are held constant, then as volume increases, quantity must increase
Charle's Law?
If quantity and pressure remain constant, then as volume increases, temperature increases
Gay-Luccais Law?
If quantity and volume remain constant, as temperature is increased, pressure increases
Boyle's Law?
If quantity, and temperature remain contant, then as volume is increased, pressure decreases.
Why does volume have to be decreased in order to maintain pressure when the temperature of 1 mole of gas in a liter container is decreased?
If the temperature is decreasing, their KE decreases, the particles slow down- they would not reach the walls as often so fewer collisions would mean a lower p- in order to keep the collision rate the same the volume is reduced (the walls moved in) so they reach them at the same rate- P remains the same
What would happen to pressure if the quantity of gas increases, and why?
It would increase, because more particles are now hitting the container's sides; P and n have a direct relationship
Explain what will happen to pressure if 2 additional moles of oxygen are added to 1 mole of Oxygen already in a liter container at 25 degrees Celsius?
More particles would mean more collisions so an increase in P.
Which gas will effuse faster, Ar or N_2? How much faster?
N_2 effuses 1.194 times faster than Ar
Which gas effuses faster at the same temperature: oxygen gas or fluorine gas?
Oxygen effuses 1.08 times faster than Fluorine
V is proportional to n at constant __ and __
P; T
Ideal Gas Law...
PV = nRT
Dalton's Law equation?
P_a + P_b + P_c =P_t
What is the SI unit for pressure?
Pa
What happens to pressure in a container when temperature increases, and why?
Pressure in the container would increase, because as temperature increases, Kinetic Energy rises, and particles speed up and collide with walls more, resulting in more pressure
What would happen to pressure in a container if volume increases, and why?
Pressure would decrease, because as volume increases, distance of moving particles hitting the container walls increases, so they get there less often, fewer collisions occur, and less pressure.
If volume increases, what must happen to quantity in order for pressure to remain the same, and why?
Quantity must increase, because as volume increases, distance increases, and collisions decrease, so more particles are needed to make up the difference
Best Ideal Gas Law form?
R = (.0821 L * atm / mol * K)
STP means...
Standard Temperature and Pressure
P is proportional to __ at constant n and V
T
P is proportional to n at constant ___ and ___
T; V
If volume is increased, what must happen to temperature for pressure to remain the same, and why?
Temperature must increase, so particles speed rises, and the particles hitting the walls makes up for the increase in volume, as the same number of particles hit the wall as previously
What does Ideal Gas Law assume?
That the gas is compressible; no Intermolecular forces working between particles (dispersion mostly)
Graham's Law?
The concept that a lighter gas (calculated based off of molar mass) will have a greater rate of effusion out of an exit point than a heavier gas
Sketch a barometer, and explain how it works?
The mercury rises or falls with a change in atmospheric pressure; As the atmospheric pressure rises. Mercury rises
Describe what causes pressure when a gas is contained in a certain volume?
The number of collisions of the gas particles with the walls of the container
Dalton's law?
The pressure exerted by a mixture of gases is equal to the sum of the partial pressures of each gas in the mixture
Graham's law equation?
The square root of the heavier gas divided by the square root of the lighter gas
P is inversely proportional to __ at constant n and T
V
T and P have a(n)_____ relationship
direct
T and V have a(n) _____ relationship
direct
R =
gas law proportionality constant
If volume, temperature, are held constant then as quantity increases, pressure ____?
increases
V and P have a(n) _____ relationship
inverse
d =??????????????????????????
m/v
P is proportional to __ at constant T and V
n
V is proportional to __ at constant P and T
n
P is inversely proportional to V at constant __ and __
n; T
P is proportional to T at constant ___ and ___
n; V
gram molar mass =
particles
F = m/a ; caused by collisions with container walls
pressure
how many particles
quantity
Effects the particle speed
temperature
What is Gas Pressure, and why does it happen?
the force exerted per unit area that results from collisions of gas particles with surrounding surfaces
(length)^3 distance particles can travel
volume
