The student will learn:

1. The five basic assumptions of the Kinetic Molecular Theory.

2. The difference between an Ideal Gas and a Real Gas

3. Four items necessary for gas conversions (volume, temperature, moles, molecules)

4. Calculations of conversion between four different pressure measurements.

atm, mmHg, mmtorr, Kpa

Gas Unit 1/5

KMTKinetic Molecular Theory

1. Gases consist of particles far apart.

2. Collisions between particles are elastic.elastic meaning = no net loss of KE

3. Gas particles are in constant, rapid, random motion

4. No forces of attraction or repulsion between gas particles.

5. Average KE of a gas depends on Temperature of gas.

If the molecules of air that surrounds us could be magnified until they were as big as tennis balls, the average distance between the molecules

would be: 1. One inch

2. 50 feet

3. 6 miles

4. 1 yard

5. 2mile

Ideal Gases: an imaginary gas that

perfectly fits all assumptions of KMT.

(Noble gases) closest thing to it

Real Gases: does not behave completely

to the laws and theories of the KMT.

Need to know 4 items for understanding Gases

Volume: liters and milliliters

Temperature: Kelvin K K = 273 + oC convert 42oC =

126oC=212oC=

Zero degrees Kelvin = absolute zerocoldest temperature never reachable

What is -10OC on the Kelvin scale?

1. 253K

2. 273K

3. 283K

4. +10K

5. None of these

Need to know 4 items for understanding Gases

Volume: Temperature:

# of moles or molecules

avogadro’s number 6.022 x 1023 molecules per mole

22.4 liters per mole @ STP

STP === standard temperature pressureOoC or 273K, 1atm

S.T.P. means….

1. -273K and 1atm

2. OOC and 1atm

3. 25Oc and 760mmHg

4. Zero Kelvin and 760mmHg

Pressure: atm atmosphere of pressure

1 atm = 760 mm Hg = 760 torr = 101.3 kpaSea level pressure = 1 atm or 760mm Hg or 101.3 kpa

STP === standard temperature pressure

OoC or 273K, 1atm

Average pressure in Denver Colorado is 0.083atm.

Exress in mm Hg and kpa

752 mmHg to atm.

3 atm to torr

780mmHg to kPa

320 kPa to atm

799 torr to atmospheric pressure

799 torr to kPa

1.78 atm to kPa

85.4 kPa to mmHg

1.83 atm to mmHg

790mmHg to kPa

123.85 kPa to atm

745mmHg to torr

The student will learn:

1. The five basic assumptions of the Kinetic Molecular Theory.

2. The difference between an Ideal Gas and a Real Gas

3. Four items necessary for gas conversions (volume, temperature, moles, molecules)

4. Calculations of conversion between four different pressure measurements.

atm, mmHg, mmtorr, Kpa

Gas Unit 1/5

The student will learn:1. Concepts concerning Boyles Law,

Charles Law, Gay-Lussac Law.

2. Calculations of gas problems using the Combined

Gas Law.PV = PVT T

Gas Unit 2/5

Boyles Law: keeping temperature same

P1V1 = P2V2

Pressure down = volume up

Pressure up = volume down

When cap comes off …pressure down

= volume up

Inversely porportioned

Down to bottom of ocean…pressure up

= volume down

• Charles Law: Pressure-Volume Inversely proportional.

Doubling the initial pressure of one liter of a gas causes the volume of the gas to :

1. Double

2. Remain the same

3. Decrease by 1/3

4. Decrease by ½

5. Triple

Charles Law: keeping pressure same

=

temperature up volume up

temperature down volume down

Balloon in freezer vs balloon next to heatCar tires in summer vs. tires in winter

V1

T1

V2

T2

Versly propoational

Gay-Lussac’s law : keeping volume same

Temperature up = pressure up

Temperature down = pressure down

Throw hair spray can in fire

P1

= P2

T1

T2

Combined Gas Laws: all 3 put together

P1V1 = P2V2

T1 T2Worksheet 11.0

1)A scuba diver at the beach has his 24 L air tank sitting outside in a temperature of 30 degree Celsius and the tank pressure registers at 12atm. As he dives down into the ocean the temperature of the water and tank drop to 10 degrees Celsius. What is the new pressure of the scuba tanks?

2. A gas has a volume of 22 liters, a pressure of 3.5 atm and a temperature of 278K. If I raise the temperature to 350K and lower the pressure to 1.5 atm. What is the new volume of the gas?

3. A balloon has a volume of 28L at the beach with standard pressure. As the balloon rises the volume changes to 30L and its temperature decreased to 15Oc . The presssure is recorded by the instrument panel to be 0.75atm at the height of its rise. What was the temperature at the beach?

4. If I have 15L of oxygen gas held at a pressure 55atm and a temperature of 800K, what will the volume of the gas if I decrease the pressure to 45atm and decrease the temperature to 775K?

5. A student was assigned to calculate the unknown volume of gas held at temperature of 75K in a container with a pressure of 60 atm. If increasing the temperature to 225 K and decreasing the pressure to 15 atm causes the volume of the gas to be 32 liters, how many liters of unknown gas did

the student calculate?

6. An aerosol can of hair spray holds 0.25 liters of spray at STP. Then a crazy chemistry student throws the can into a campfire, which is 1400 degrees Celsius. How much pressure may be generated? What will determine if the can explodes?

Ws.11.0

The student will learn:1. Concepts concerning Boyles Law,

Charles Law, Gay-Lussac Law.

2. Calculations of gas problems using the Combined Gas Law.

PV = PVT T

Gas Unit 2/5