[Pirulli Chemistry] Name: __________________________________________ Per: ________ Date: 1/28/20

Gas Law Graphing YOYO: Convert the following temperature measurements from Celsius to Kelvin

15 °C = _______________ 100 °C = ______________ 0 °C = _______________ 38 °C = _______________

Boyle’s Law

Robert Boyle (1627-1691), an English chemist, discovered that doubling the pressure of an enclosed sample of gas while keeping its temperature constant caused the volume of the gas to be reduced by half. Boyle’s Law states that the volume of a given mass of gas varies inversely with the pressure when the temperature is kept constant. An inverse relationship means that as one variable increases in value, the other variable decreases. Graph the following values on the graph to the right:

Pressure (mm Hg) 1200 600 300 200 150 120 100

Volume (mL) 380 760 1520 2280 3040 3800 4560

Questions:

1. What does Boyle’s Law state?

2. What type of relationship is this? (direct or indirect?)

3. Cross out the value in the combined gas law that is held constant in Boyle’s Law. Rewrite the equation as the equation for Boyle’s Law.

Combined gas law:

The equation for Boyle’s Law:

4.

As the pressure is increased, the volume __________. As the pressure is decreased, the volume __________.

5.

As the volume is increased, the pressure __________. As the volume is decreased, the pressure __________.

6. Sulfur dioxide (SO2), a gas that plays a central role in the formation of

acid rain, is found in the exhaust of automobiles and power plants. Consider a 1.53-L sample of gaseous SO2 at a pressure of 5.6 kPa. The pressure is changed to 15 kPa at a constant temperature.

a. What will be the new volume of the gas?

b. As the pressure ______________, the volume ______________.

1

decreased

decreased

increased

increased

increaseddecreased

Boyle’s Law states that the volume of a given mass of gas varies inversely with the pressure when the temperature is kept constant.

 

Charles’ Law French physicist Jacques Charles (1746-1823) studied the effect of temperature on the volume of a gas at constant pressure. Charles’s Law states that the volume of a given mass of gas varies directly with the absolute temperature of the gas when the pressure is kept constant. The absolute temperature is temperature measured with the Kelvin scale. The Kelvin scale must be used because zero on the Kelvin scale corresponds to a complete stoppage of molecular motion. Graph the following values on the graph to the right:

Temperature (K) 700 600 500 400 300 200 100

Volume (mL) 1400 1200 1000 800 600 400 200

Questions:

1. What does Charles’ Law state?

2. What type of relationship is this? (direct or indirect?)

3. Cross out the value in the combined gas law that is held constant in Charles’ Law. Rewrite the equation as the equation for Charles’ Law.

Combined gas law:

The equation for Charles’ Law:

4.

As the temperature is increased, the volume ____________. As the temperature is decreased, the volume ___________.

5.

As the volume is increased, the temperature ____________. As the volume is decreased, the temperature ___________.

6. A sample of gas at 158 ℃ and 1 atm has a volume of 2.58 L.

a. What volume will this gas occupy at 388 ℃ and 1 atm?

b. As the temperature ______________, the volume ______________.

2

increased

increased

increased increased

decreased

decreased

Charles’s Law states that the volume of a given mass of gas varies directly with the absolute temperature of the gas when the pressure is kept constant.

 

Gay-Lussac’s Law French chemist, Joseph Gay-Lussac (1778-1850), discovered the relationship between the pressure of a gas and its absolute temperature. Gay-Lussac’s Law states that the pressure of a given mass of gas varies directly with the absolute temperature of the gas when the volume is kept constant. Gay-Lussac’s Law is very similar to Charles’s Law, with the only difference being the type of container. Whereas the container in a Charles’s Law experiment is flexible, it is rigid in a Gay-Lussac’s Law experiment. Graph the following values on the graph to the right: Questions

1. What does Gay-Lussac’s Law state?

2. What type of relationship is this?

3. Cross out the value in the combined gas law that is held constant in Gay-Lussac’s Law. Rewrite the equation as the equation for Gay-Lussac’s Law.

Combined gas law:

The equation for Gay-Lussac’s Law:

4.

As the temperature is increased, the pressure ___________. As the temperature is decreased, the pressure ___________.

5.

As the pressure is increased, the temperature ___________. As the pressure is decreased, the temperature ___________.

6. The gas in an aerosol can is under a pressure of 3.00 atm at a temperature of 25 ℃. It is dangerous to dispose of

an aerosol can by incineration. a. What would the pressure in the aerosol can be at a

temperature of 845 ℃?

b. As the temperature ______________, the pressure ______________.

3

increased

increased

increased increased

decreased

decreased

direct

Gay-Lussac’s Law states that the pressure of a given mass of gas varies directly with the absolute temperature of the gas when the volume is kept constant.

 

Combined Gas Law *If a question gives you the temperature, volume, AND pressure, you must use all the values when calculating the answer. This means that you are NOT crossing anything out of the combined gas law.

1. A sample of gas occupies a volume of 50.0 milliliters in a cylinder with a movable piston. The pressure of the sample is 0.90 atmosphere and the temperature is 298 K. What is the volume of the sample at STP?

2. A 220.0-mL sample of helium gas is in a cylinder with a movable piston at 105 kPa and 275 K. The piston is pushed in until the sample has a volume of 95.0 mL. The new temperature of the gas is 310 K. What is the new pressure of the sample?

3. Which graph represents the relationship between pressure and temperature for a sample of an ideal gas at constant volume?

A) B) C) D)

4. Which graph represents the relationship between pressure and volume for a sample of an ideal gas at constant temperature?

A) B) C) D)

5. Which graph represents the relationship between temperature and volume for a sample of an ideal gas at constant pressure?

A) B) C) D)

4

 

Temperature (K) 100 150 200 300 400 450

Pressure (atm) 0.2632 0.3947 0.5263 0.7895 1.0526 1.1842

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