LAB 9: PROPERTIES OF GASES
Part 1: Gas Laws: Diffusion, Volume, Temperature, And Pressure
Purpose and Concepts:
States of Matter; Vaporization:

Practice liquid to vapor conversions in the study of properties of gases.
Graham’s Law:


Illustrate the relationship between the mass of a gas and its rate of diffusion through air and
relate to aromas in baking.
To predict the relative rate of diffusion of ammonia (NH3) and hydrogen chloride (HCl) gases.
Charles’ Law:


Illustrate the relationship between the volume (V), and Temperature (T) of gases.
To relate the properties of gases to canning and cooking cream puffs.
Boyle’s Law:

Illustrate the relationship between the pressure (P), and volume (V), of gases and relate to high
altitude cooking.
Reading:
Phases: “On Food & Cooking” pp.816-818
Aromas: “On Food & Cooking” pp. 272-273; 387
Cream Puff Pastry, Pate a Choux: “On Food & Cooking” pp.552-553
Baking at High Altitudes: “On Food & Cooking” p. 559
Supplies needed: (*Included in your chemistry kit.)
Demo of Graham’s Law::
Long tubing w/ stoppers
Con NH3 & Con HCl
Cotton balls
Meter stick
Hot plate
Vacuum flasks w/ tubing & stoppers
Balloons
Marshmallows
Sealed capillary tubes
Colored water w/ syringe
Grease pencil
Canning jars
Metal pans for heating
400 mL food beaker
Bowl
Wisk or spoon
Measuring cups
Cookie sheet/brownie pan
For Cream Puffs:
Butter (2 Tbl each grp)
Flour (1/4 c each grp)
Egg (1 each)
Discussion:
Volume, Pressure, and Temperature:
Volume, the amount of space taken up by a substance, is described for liquids by the metric units of liters (L), and milliliters
(mL), and for solids by the units of cubic centimeters (cm3). The common units of our culture, pints (pts), quarts (pts), and gallons (gal), are
rarely used in science.
Pressure, the amount of force on an object (or the quantity of collisions with a surface), is measured in atmospheres
(atm), millimeters of mercury (mmHg), and Torr. Pressure is measured using a barometer in which a pool of liquid mercury (Hg) is
pushed up into a glass vacuum tube by the force of the earth’s atmosphere pushing down on it. The height of the mercury in the column is
measured in millimeters (mm). One atmosphere of pressure causes the mercury to rise in the vacuum tube to a height of 760 mm or 760
torr (1 atm = 760 mmHg = 760 torr). The culturally common unit of pressure, pounds per square inch (psi) is uncommon in
educational science.
We will vary the laboratory pressure using either vacuum lines on the bench tops, or aspirator nozzles on the sink faucets. When a
stoppered vacuum flask is attached to one of these vacuum sources the number of collisions of gas inside the flask decreases thus decreasing
the pressure.
Temperature in science is measured using the Celsius (oC) and Kelvin (K) scales. Celsius and Kelvin degrees measure the
o
same quantity, (a Celsius degree and a Kelvin degree are the same size) they just start at different points, (K = C + 273). When solving
mathematical problems involving temperature, the units must always be in Kelvin. The common temperatures of the daily weather reports
in the United States are reported using the Fahrenheit (oF) scale which is not used in science.
The volumes of solids and liquids are only minimally affected by pressure (P) or Temperature (T). Gases, however, behave much
differently than solids or liquids in that their Volume (V) significantly expands or contracts with changes in Pressure (P) and Temperature
(T).
In the laboratory exercises that follow you will discover the relationships between Volume (V), Pressure (P), and Temperature (T)
and be able to derive Boyle’s Law, Charles’ Law, and Gay-Lussac’s Law of gases for yourself.
Direct vs. Inverse Relationships:
CH117 Lab 9 Gases (F16)
1
When one property (lets call it property A) influences another property (call it B) to change there are two possibilities for how the
change could occur.
A direct relationship between properties means that if property A increases (goes up) then property B increases (goes up) also;
Or likewise, if A decreases (goes down) then B also decreases (goes down). Properties A and B in a direct relationship are like 2 sides of a
barbell. When a weight-lifter raises or lowers the bar both A and B move up or down together.
An inverse or indirect relationship between properties means that if property A increases (goes up) then property B decreases
(goes down); Or likewise, if A decreases (goes down) then B increases (goes up). Properties A and B in an inverse relationship are like 2
sides of a seesaw. When one side goes down, the other goes up.
Of course not every property is related to every other property. Sometimes events are totally unrelated. The scientific method and analysis
of experimental testing can help to determine if properties are related or not.
A
B
B
A
Inversely or Indirectly Related
Directly Related
Notes:
Procedures:
I. Graham’s Law: (Instructor’s Demo)
8
The tube must be clean and scrupulously dry. Water present
will absorb the gases and prevent them from diffusing.
MW vs Rate of Diffusion
1. Obtain a 100 cm length of 12 mm diameter dry8 glass
tubing, two cork stoppers to fit the ends, and two
cotton plugs.
2. With a dropper place about 10 drops of concentrated
hydrochloric acid (12M HCl)9 to one of the cotton
plugs.
3. With a separate dropper, add 10 drops of concentrated
ammonium hydroxide (NH4OH)10 to the second
cotton plug.
HCl
NH3
9
Use extreme caution when dealing with concentrated acids or
bases. If you get any on your skin wash immediately with
copious amounts (lots) of water.
10
Ammonium hydroxide, NH4OH, is a solution of ammonia,
NH3, dissolved in water, H2O. Ammonia gas easily escapes the
water solution to travel as a gas.
11
You want the gases to start traveling at exactly the same time.
This is a race between two gases. We are trying to see if one
gas will travel faster than the other gas.
12
4. With forceps or rubber gloves9, simultaneously11
insert the cotton plugs into each end of the glass
tubing and stopper the ends.
The molecules of gas are in constant random motion which
enables them to move and occupy any volume available or mix
spontaneously with other gases. When HCl and NH3 meet they
will react to form white solid NH4Cl according to the equation:
5. Immediately place the tube on a flat surface and do
not disturb it. Record the time. (Box II5)
13
6. Note the time required for a white ring to appear (Box
II6) and mark the ring with a grease pencil. 12
7. Measure and record (II7) the distance between the
ring and the nearest edge of each cotton plug. Use
these measurements to calculate the relative rate of
diffusion13 and compare to theoretical values. 14
2
HCl(g) + NH3(g)  NH4Cl(s)
Light molecules (gases of lower molecular mass) have a
greater velocity (move faster) than heavier gases. Thomas
Graham, in 1829, formulated the following calculation called
Graham’s law of diffusion:
Rate of diffusion gas X =
Rate of diffusion gas Y
14
MW gas Y
MW gas X
To get the theoretical values for the rate of diffusion of NH3
compared to the rate of diffusion of HCl just insert the molar
masses (MW’s) into the Graham’s law equation. Let’s let X be
NH3 (17.0 g/mol) and let Y be HCl (36.5 g/mol).
CH117 Lab 9 Gases (F16)
Notes:
Procedures:
II. Charles Law:
A. Volume vs Temperature
19
1. Take a glass capillary tube that has been sealed at one end. Using a tiny dropper
or syringe with a blunt needle, inject a drop of colored water into the center of
the tube so that air is trapped inside the tube.
2. Holding the tube of trapped air near the mouth of the tube.19 carefully draw a line
at the lower edge of the colored water with a marking pencil.
3. Hold the tube at the top, above the marked line, and immerse it in a beaker of ice
water. Observe the pocket of trapped air and record your results on the report
sheet.20
4. Now, take the tube out of the ice water and immerse it in a beaker of hot tap
water. Observe the pocket of trapped air and record your results on the report
sheet.
The tube should be held at
near the mouth to avoid
warming the trapped air with
your hands. If you hold the
tube at the bottom then your
body temperature is warming
the trapped air and may alter
your results.
20
Indicate increasing volume
(V) with up arrows, and
decreasing volume (V)
with down arrows. Indicate
any increase in temperature
with up arrows (T) and
decrease in temperature with
down arrows (T).
5. Formulate Charles’ Law by summarizing your results in the space
provided on the report sheet.
6. Dispose of the glass capillary tube in the glass or “sharps” waste container. Do
not put it into the regular garbage cans.
B. Charles Law: Practical Application 1: Cream Puffs:
Gas Leavening and the Maillard Reaction
1. Preheat oven to 425oF.
2. Heat together to a rolling boil in a large food beaker
 ¼ cup (60 mLs) water and
 1/8 cup (2 Tbl) margarine or butter.
21
Egg protein in the dough
should react with the flour
carbohydrates in the cream
puff dough to produce a
golden
brown
color
(Maillard reaction). We are
adding even more protein
(from egg or milk) to
determine if more protein
can make an even darker
puff.
22
3. Stir in vigorously over low heat until mixture forms a ball. (about 1
minute).
 ¼ cup all-purpose flour
Frost
or
dust
with
powdered sugar if desired.
4. Remove from heat and transfer the flour/butter ball to a mixing bowl.
5. Add and beat until smooth
 1 egg
6. Drop dough by spoonfuls about 3 inches apart onto an ungreased cookie
sheet.
7. Brush half of your cream puffs with a solution of eggwhite or milk and
leave the other half plain.
8. Bake all together at 400oC until puffed and golden (about 35-40 minutes).
9. Make note of any color difference between those brushed with milk or
eggwhite and those left plain.21
10. When cool enough to handle .cut off tops and fill puffs with filling of
choice (ice cream, pudding, fruit pie filling, yogurt…...)22
CH117 Lab 9 Gases (F16)
3
C. Charles Law: Practical Application 2: Canning Food
1. Place a pint Pyrex canning jar or bottle containing about one half
inch of water23 in a pot of boiling water, or in a microwave oven.
2. Heat the jar until steam (gaseous water) steadily comes from the jar.
3. Carefully tighten the lid of the hot jar and set it away from the heat
to cool.24 (Go on with other parts of the lab as this will take a while.)
4. Observe the effects of cooling on the gases in the jar. Record your
observations of both heating and cooling on the report sheet.
III. Pressure (Vacuum):
1. Attach the benchtop vacuum source25 to the side arm of a 250 mL vacuum
flask using heavy walled tubing. 26
2. Place the palm of your hand over the top of the vacuum flask and then turn
on the vacuum line or aspirator water full force. Observe the effect of the
vacuum on your hand.
3. Complete the drawing on the report sheet by adding your hand and the
vacuum line. Indicate on the inside and outside of the flask drawing the
locations of high pressure (P) with up arrows, and locations of low
pressure (P) with down arrows.
IV. Boyle’s Law: Volume vs Pressure
23
If you were really canning then
your jar would contain food stuffs
and water solution with about a ½
inch air space at the top. A jar that
full would take longer to heat than
the time allotted in lab so we use a
jar with only a little water just to
illustrate the process in a shorter
time.
24
It is best to leave the hot jar at
room temperature to allow it to cool
slowly rather than cooling fast with
cold water or ice. If a hot jar cools
too suddenly the glass may break.
25
If using a sink aspirator do not
attach the vacuum tube to the spout
that gives water. When the water is
turned on no water should enter the
vacuum flask.
26
If you use regular strength rubber
tubing instead of the heavy walled
vacuum tubing your tube will go flat
under reduced pressure (vacuum).
27
4. Slightly inflate a small balloon just large enough so that it can be placed
inside your 250 mL vacuum flask. Knot it tightly, and insert the balloon
into the vacuum flask. Cap the flask tightly with a rubber stopper.
5. Turn on your vacuum source full force. On the report sheet record your
observations.
6. Detach the vacuum tubing27 to let atmospheric pressure into the vacuum
flask. Record your observations.
7. Repeat steps 1-3, but instead of a balloon place a marshmallow inside the
flask. Report your results.
8. Formulate Boyle’s law by summarizing your results in the blanks given on
the report sheet.
4
Notes:
CH117 Lab 9 Gases (F16)
If you are using the benchtop
vacuum lines you may turn the
vacuum off before detaching the
tubing from the flask.
If you are using the sink aspirators
then do not turn off the aspirator
water until you have removed the
tubing to release the vacuum. If low
pressure (vacuum) were to exist in
the flask at the time that the water is
turned off then water will get pulled
from the sink back into the flask.
.
LAB 9: PROPERTIES OF GASES
Part 2: Gas Laws: Solubility; Root Beer
Purpose and Concepts:
States of Matter; Sublimation:

Use dry ice to illustrate sublimation of a solid to a vapor.
Solubility of Gases:



Henry’s Law; Observe the solubility of gases in water with varying pressures.
Observe the solubility of gases in water with varying temperature.
Make root beer to illustrate the solubility of gases related to temperature and pressure.
Reading:
Phases: “On Food & Cooking” pp.816-818
Flavor Chemicals in Root Beer/Sassafras: “On Food & Cooking” p. 259, 409
Supplies needed: (*Included in your chemistry kit.)
* flasks, beakers, or cups
*graduated cylinder
*Gram kitchen scale
*Thermometer
Microwave or hotplate
Vacuum flask w/ stopper & tubing
Carbonated beverage
Funnel
Cloth kitchen towel
Small paper cups (Dixie bathroom size)
For Root Beer
250-355 mL plastic bottle w/ screw cap
25g Sugar
4 mL Root beer extract
~20 g Dry ice (crushed in a towel with a
hammer )
Discussion:
Sublimation occurs when a solid converts to a vapor (gaseous state) directly without becoming a liquid first.
Solid water (ice) will sublime when the temperature and pressure are just right. Solid carbon dioxide (dry ice)
easily sublimes at room temperature and normal atmospheric pressure.
Solubility of Gases: Gases generally have low solubility in water because a gas wants to expand to fill all the
space provided rather than to be constrained within a liquid. We can force a gas to dissolve by increasing the
pressure. When solid carbon dioxide sublimes into a gas it increases in volume and so in a closed container will
increase the pressure. When the pressure increases this forces gaseous CO2 to enter the liquid water and make a
carbonated solution
.
Notes:
PROCEDURES:
ACTIONS:
1
Indicate
I. Solubility of Gases:
A. Henry’s Law: Solubility of CO2 vs Pressure
1. Pour ice cold10 carbonated water (CO2 dissolved in H2O) into a vacuum
flask to a level of about 1 inch.
increasing
solubility
(S) of CO2
gas with up arrows, and
decreasing solubility (S) of CO2
gas with down arrows. )
(Ability of gas to dissolve)
2. Connect the flask to the vacuum source and turn it on full force. And
observe any bubbles formed; an indication of the change in the solubility
of CO2 in water. Record your observations.1
3. Detach the vacuum tubing from the source to allow the flask to return to
atmospheric pressure. Record your observations..
4. Formulate Henry’s Law by summarizing your results on the report
sheet.
CH117 Lab 9 Gases (F16)
5
NOTES:
PROCEDURES:
B. Solubility of CO2 vs Temperature
2
1. Obtain 2 Erlenmeyer flasks, beakers, or cups of equal size.
2. Into one of the flasks pour carbonated water (CO2 dissolved in H2O) to
a level of about 1 inch.
3. Into the second flask put an equal volume of tap water and a
thermometer.
4. Place the two flasks side by side on a hot plate and heat but do not boil.
(Do not let the tap water approach 100oC).
To “tare” the beaker means to set the
mass of the beaker to zero. This way
when you add materials to the beaker
you can read the mass of materials
added directly. If you do not “tare” the
beaker then you would have to subtract
the mass of the beaker from the total
mass in order to determine the mass of
materials inside.
3
Sucrose = table sugar.
4
5. Observe any bubbles formed; (an indication of change in the solubility
of carbon dioxide in water) and record the results14
Root Beer Extract = solution of
caramel color, corn syrup, wild cherry
bark extractives, methyl salicylate,
vanillin, etc.
5
Solid carbon dioxide = CO2 = dry ice.
C. Solubility of CO2: Practical Application; Root Beer:
1.
To have ingredients ready when needed measure out the following in
separate containers and set aside to add when directed.



2
Place a 150 mL beaker on your balance and “tare” it. Add to the beaker
25g of granulated sucrose.3
Measure 4 mL of root beer extract 4(measure into a graduated cylinder then set
6
You don’t have to have exactly 20-25
grams. The amount of gas preferred in
a soda is a matter of taste but usually
the more the better.
aside until needed)
Place a 400 mL beaker on your balance and “tare”2 it. Add to the beaker
crushed solid carbon dioxide (CO2).5 (about 20-25 g)6
7
This allows enough room in the bottle
to added dry ice and still have room to
mix.
2. Obtain a small (250 or 355 mL is OK) plastic bottle with screw on lid.
3. Add to the bottle
 25 g granulated sucrose3, (use a funnel to avoid spilling)
 2 mL Root Beer Extract.4
4. Add to the bottle
 about 200 -250 mLs water (It doesn’t have to be exact. You can
add more later if the root beer is too concentrated.)
8
You should feel the plastic bottle
getting rigid with the increased
pressure from the gas transitioning
from a solid (relatively low volume) to
a gas (relatively high volume). (Note
that 1 lb of CO2 solid would fill about
64 gallons of volume or 243 L!)
9
5. Cap and shake to mix until the sucrose is dissolved in the water.
Pour a small sample into a paper cup
to taste to determine the desired amount
of carbonation.
6. To the solution spoon in between 3 and 4 grams of solid CO2. Quickly
replace the cap tightly, wrap the bottle in a cloth towel and shake
vigorously.8
7. After a few (3-4) minutes of shaking, open the lid carefully to allow any
extra gas to escape and add another several grams of CO2 . Cap and
shake as before.
8.
Continue adding additions of CO2 (2-3 grams at a time) until the desired
“mouth feel” of carbonation has been reached.9
9. Describe your root beer including the taste, temperature, and texture.
CH117 Lab 9 Gases (F16)
6
LAB 9: PROPERTIES OF GASES
Part 3: Carbon Dioxide: Density and Flammability
Purpose and Concepts:
States of Matter; Sublimation:

Use dry ice to illustrate sublimation of a solid to a vapor.
Properties of Carbon Dioxide:


Illustrate the density of carbon dioxide compared to air.
Observe the ability of carbon dioxide to put out fire.
Reading:
Phases: “On Food & Cooking” pp.816-818
Supplies needed: (*Included in your chemistry kit.)
*400 mL beaker
*Gram kitchen scale
*graduated cylinder
Matches
Small birthday candle
Cardboard or card stock paper
Dry Ice
Gloves& hammer for dry ice
Zip lock baggie
Sodium bicarbonate
Vinegar
Discussion:
Sublimation occurs when a solid converts to a vapor (gaseous state) directly without becoming a liquid first.
Solid water (ice) will sublime when the temperature and pressure are just right. Solid carbon dioxide (dry ice)
easily sublimes at room temperature and normal atmospheric pressure.
CH117 Lab 9 Gases (F16)
7
NOTES:
PROCEDURES:
1
ACTIONS:
I. Carbon Dioxide:
A. Preparation and Flammability of Carbon Dioxide (CO2):
1. Make a candle holder by cutting a small X (about 1 cm slits) in the
center of a 5 cm2 (2 in2) piece of heavy card stock paper. 1
Or make a small hole in the center of a 5 cm2
piece of corrugated cardboard.
2
Make sure the candle stands upright in the
beaker.
2. Insert a birthday candle into the paper holder and place it in the
bottom of a 250 or 400 mL beaker so that the candle stands upright.2
3. Cover the bottom of the beaker (over the card if needed) with about3
10 g (1 tablespoon) of baking soda (sodium bicarbonate, NaHCO3).
3
4. Obtain about 20 mL of vinegar (5% acetic acid, HC2H3O2).
3
It is not necessary to accurately measure the
quantity as this is a qualitative not a
quantitative procedure.
4
5. Light the candle4.
6. Slowly pour the vinegar down the inside edge of the beaker being
careful not to pour it on the candle. Observe and record the effect of
any reaction and write the chemical equation for this reaction.
It may be necessary to hold a lighted match
with tongs to light the candle inside the
beaker.
5
Baking soda and acids (such as vinegar) react
to make carbon dioxide gas according to the
following equation:
7. Observe and record the effect of the resulting gas5 on the flame. If
the candle goes out, try to relight it4. Record your observations.
NaHCO3(s) + HC2H3O2(aq)  NaC2H3O2(aq)
+ H2O(l) + CO2(g)
B. Sublimation and Relative Density of CO2:
Carbon dioxide gas can extinguish a fire by
displacing the oxygen in the air around
the burning object. When oxygen is
removed the fire goes out.
Practical Application: Fire Extinguisher
1. Using tongs or insulated gloves6, place a small piece (about the size
of a large marshmallow) of solid carbon dioxide (dry ice7) in a quart
size zip-close plastic bag.
6
Don’t touch dry ice with your bare skin; the
extreme cold can cause serious skin damage.
1
2. Flatten the bag to remove as much air as possible and seal the bag
shut.
3. Allow the dry ice to slowly warm up to room temperature. Observe
and record your observations.
4. Insert the birthday candle and holder made in Part VA into the
bottom of a clean 250 or 400 mL beaker. Light the candle4.
5. Carefully hold your bag of sublimed dry ice over the burning candle
and pour the gas onto the flame. Observe and record your
observations making note of the density of carbon dioxide gas
compared to the density of air (a mixture of mostly nitrogen gas and
oxygen gas).8
For fun you may also choose to put a chunk
of dry ice into a latex rubber glove or a
balloon. Evacuate the air and tie a knot to
keep closed.
7
Although carbon dioxide is a gas at room
temperature, it is a solid below -78.5oC (100.3oF). Solid carbon dioxide is called “dry
ice” since it changes from solid to gas without
forming a liquid in a process called
sublimation.
8
Optional: While there is still CO2 in your
beaker try blowing soap bubbles into the
beaker and see if they drop to the bottom or
“float” .
Soap bubbles may appear to “float” but really
they are resting on top of the carbon dioxide
gas.
CH117 Lab 9 Gases (F16)
8
Lab 9: Properties of Gases
Name___________________
Partner_________Date___
Part 1: Gas Laws Report:
I. Graham’s Law: MW vs Rate of Diffusion
Prediction:
Molar Mass (MW) of
MW of NH3(g)
MW of HCl(g)
HCl(g) and NH3(g)
Prediction: Who
should travel faster?
Why?
Results:
Race between
HCl(g) and NH3(g)
Distance traveled
Observations: What did you see? How is distance determined?
By NH3(g)
By HCl(g)
(to nearest 0.1 cm)
Experimental value of
Show calculations:
cm traveled by NH3
cm traveled by HCl
=
rate of diffusion of NH3
rate of diffusion of HCl
Theoretically Ammonia (NH3) gas should travel about 1.5 times farther than Hydrochloric acid vapors
(HCl) in the same amount of time (or 1.5 times faster). How do your experimental results compare to
this?
Explanation and
Analysis:
Was your prediction correct? Explain any anomalies or issues with the experiment.
Application:
You are standing in the middle of a room.


In one corner of the room someone is cutting up apples that give off aromas made of volatile 6-carbon alcohols
& aldehydes.
In the opposite corner of the room someone is cutting a melon which gives off aromas made of volatile 9-carbon
alcohols & aldehydes.
___1. If both persons start cutting their fruits at the same time which will you smell first?
A. apples
B. melon
C. both at the same time
Explain your answer:
CH117 Lab 9 Gases (F16)
9
II. Charles’ Law:
A. Volume vs Temperature
Action
Observations
Effect on
Temperature
T or T
Effect on
Volume
V or V
Trapped air immersed
in ice water.
Trapped air immersed
in hot water.
Formulate Charles’ Law by summarizing your results
Explanation &
Analysis
Explain any anomalies or issues with the experiment.
Conclusion Summary:
__1.
__2.
The volume of a gas _____ as the temperature _____.
A. decreases, increases
B. increases, increases.
C. does not change, changes
Charles’ Law: The volume of a gas ____________ the temperature.
A. varies directly with
B. varies inversely with
C. is unrelated to
B. Practical Application 1: Cream Puffs
Action
Observations
Effect on
Temperature
Effect on
Volume
T or T
V or V
Cream Puff batter
Before heating
Cream Puff batter
After heating
Summarize from your results the chemistry of the rising of cream puffs relating to Charles’ Law:
Explanation &
Analysis
Summarize any differences between the cream puffs brushed with milk/egg protein and those left plain.
Explain any anomalies or issues with the experiment. What should have happened?
CH117 Lab 9 Gases (F16)
10
Charles’ Law Continued
The Chemistry of a Cream Puff: Using your own words explain the science happening in the making of
a cream puff. (Remember 1) gas laws, and 2) gluten proteins, 3) Maillard reactions, and any other applicable
chemistry.)
C. Practical Application 2: Canning
Action
Observations
Effect on
Temperature
T or T
Effect on
Volume
V or V
Water vapor heated in
canning jar
Trapped water vapor
cooling in canning jar
Summarize from your results the chemistry of canning relating to Charles’ Law:
Explanation &
Analysis
Explain any anomalies or issues with the experiment.
CH117 Lab 9 Gases (F16)
11
III. Vacuum:
(circle one)
P or P
Inside
(circle one)
P or P
Outside
IV. Boyle’s Law: Volume vs Pressure
Action
Observations
Effect on
Pressure
P or P
Effect on
Volume
V or V
a. Vacuum source turned
on with balloon in flask.
b. Vacuum hose detached
(Vacuum source off) with
balloon in flask.
c. Vacuum source turned
on with marshmallow in
flask.
d. Vacuum hose detached
with marshmallow in flask.
Formulate Boyle’s Law by summarizing your results
Explanation &
Analysis
Explain any anomalies or issues with the experiment.
Conclusion/Summary:
1.___ The volume of a gas _____ as the pressure _____.
A. decreases, increases
B. increases, increases.
C. does not change, changes
2.___ Boyle’s Law: The volume of a gas ____________ the pressure.
A. varies directly with
B. varies inversely with
C. is unrelated to
CH117 Lab 9 Gases (F16)
12
Lab 9: Properties of Gases
Name__________________
Partner_________Date___
Part 2: Solubility Report:
I. Solubility of Gases:
A. Henry’s Law: Solubility vs Pressure
Action
Observations
Effect on
Pressure
Effect on gas
Solubility
P or P
S or S
a. Vacuum source turned on
with carbonated solution in flask.
b. Vacuum hose detached with
carbonated solution in flask.
c. A carbonated beverage is
opened on a mountain
d. A carbonated beverage is
opened below sea level
Imagine what you would see.
Imagine what you would see.
https://www.youtube.com/watch?v=EJiUWBiM8HE
e. Conclusion:
1.___ The solubility of a gas in water (the ability of a gas to dissolve) _____ as the pressure _____.
A. decreases, increases
B. increases, increases.
C. does not change, changes
2.___ Henry’s Law: The solubility of a gas ____________ the pressure.
A. varies directly with
B. varies inversely with
Explanation/Analysis: Were your results as expected?
C. is unrelated to
Explain specifics. Explain anomalies.
B. Solubility vs Temperature
Action
Observations
Effect on
Temperature
Effect on gas
Solubility
T or T
S or S
a. Carbonated water at cold
temperature
b. Tap water at cold
temperature
c. Carbonated beverage
warmed
d. Tap water warmed
e. Conclusion:
3.___ The solubility of a gas in water (the ability of a gas to dissolve) _____ as the temperature _____.
A. decreases, increases
B. increases, increases.
C. does not change, changes
4.___ The solubility of a gas ____________ the temperature.
A. varies directly with
B. varies inversely with
Explanation/Analysis: Were your results as expected?
C. is unrelated to
Explain specifics. Explain anomalies.
CH117 Lab 9 Gases (F16)
13
Lab 9: Gases
Related Questions: Part 1 and Parts 2A & 2B
1. Vocabulary: Match the following words with the term that best describes them:
A. The ability of a substance to dissolve.
B. The force of molecular collisions on a
container.
C. The change of a solid state directly into a
gaseous state without becoming liquid.
D. Sucrose
______ Granulated Sugar
______ Sublimation
______ Solubility
______ Pressure
2. A. Which gas will diffuse faster: (Circle one)
B. Which gas will diffuse faster: (Circle one)
Methane (CH4) or Helium (He)?
Ammonia (NH3) or Hydrogen Sulfide (rotten egg smell; H2S)?
3.
A. List 2 factors that influence the solubility of a gas in a liquid?
B. Describe how each of these affect the solubility of a gas in a liquid.
Factor affecting Solubility of Gas in water
Description of that effect
4.
Water from the tap that has been boiled and then cooled again tastes flat compared to regular tap water at the same
temperature that has never been boiled. Explain why.
5.
Fish breathe the oxygen gas that is dissolved in water.
A. What happens to the amount of dissolved oxygen in a stream that gets too warm? _____________
B. What happens to the fish and why?
II. Which of the following gas laws best applies to each situation listed below?
B. Boyle’s Law
H. Henry’s Law
C. Charles’s Law
L. Gay-Lusac’s Law
G. Graham’s Law
T. Solubility vs Temperature
N. None of these
_____1.
A balloon bursts at high altitudes.
_____2.
A cake rises when it is baked.
_____3.
The shampoo bottle in your suitcase breaks open on an airplane flight.
_____4.
The aroma of baking bread travels through a home.
_____5.
Food can be cooked faster using a pressure cooker.
_____6.
Tennis balls in Denver, CO are filled with less air than tennis balls in Oregon.
_____7.
Aerosol spray cans should be stored in a cool place.
_____8.
_____9.
Two containers, one filled with chlorine and the other filled with hydrogen sulfide (H 2S), simultaneously develop
leaks. The odor of hydrogen sulfide is detected before the odor of chlorine.
Rapid ascent in an unpressurized airplane may cause intestinal cramps.
_____10.
Gas is evolved when the cap is removed from a cola drink.
_____11.
Cake batter overflows the pan when baked on a mountain but not at sea level.
_____12.
A carbonated beverage spews more when opened on a mountain than when opened in a submarine.
_____13.
Warm pop tastes flat.
CH117 Lab 9 Gases (F16)
14
Lab 9: Properties of Gases
Name__________________
Partner_________Date___
Part 2 Continued: Solubility Report:
C. Solubility of Gases Cont.: Practical Application: Root Beer
Observations & Quality of Product:
Describe the properties of your resulting Root Beer. (For example: appearance,
flavor, carbonation, temperature, etc.…….)
Analysis: Critique the experiment.
What worked well and what might be improved? For example be specific about what ways
you might change the procedures in order to make better Root Beer.
Part 3 Properties of CO2 Report
I. Carbon Dioxide: Flammability
Action
Observations/Results
a. Vinegar (HC2H3O2) mixed with
Baking Soda (NaHCO3) effect
on candle
b. Effect of CO2 on flame
c. Attempt to relight flame.
d. Chemical Equation for CO2
production from vinegar &
baking soda
HC2H3O2 + NaHCO3 
Action
Observations/Results
e. Dry Ice warmed to room
temperature (sublimation)
f. Effect of CO2 poured onto a
flame
Conclusion:
Color/Odor
Effect of CO2 on Fires
Properties
of CO2
Density
Check one:
____lighter than air
____heavier than air
____the same density as air
What conclusions can you make about the volume of gaseous carbon dioxide gas compared to solid carbon dioxide?
In your own words describe what happens on a molecular level when solid carbon dioxide becomes a gas. (Sublimes)
CH117 Lab 9 Gases (F16)
15