Gas Law Assignment
(Note: for these questions, you must remember the conversion between units of volume
1 dm3 = 1 L)
1.
Sassy Sarah’s silver sphere is subjected to a pressure of 90.3 kPa at a temperature
of 2.00 C. What will the new ssssphere pressure be if the temperature drops to a
frigid –35.0C?
Ans: P1 = 90.3 kpa
T1 = 2 degrees = 275 kelvin
P2 =
T2 = -35 degrees = 238 kelvin
P1/t1 = p2/t2
P2 = 90.3 X 238/275 = 78.15 kpa
2. Raman ran when he heard the pop of his prized perfect purple balloon. Fortunately,
Raman found that the prized 350 cm3 balloon was still secure in its 19.0 C container.
Just to be on the safe side Raman increased the temperature inside the container
to a more comfortable balloon temperature of 41.0C. Raman didn’t want the balloon
to get cold. What is the final volume of Raman’s balloon?
Ans:V1/T1 = V2/T2
350/(19+273) = V2/(41 + 273)
V2 = 350 X (41 + 273)
(19 + 273)
= 376.36 cubic cm
3. Crafty Khurram took Raman’s prized perfect purple balloon to conduct some most
unsavoury experiments. Khurram wanted to see if the balloon really did obey Boyle’s
Law. When Khurram took the balloon it was a full 375 cm3 at standard pressure.
Khurram increased the pressure to 995 kPa. What was the final volume of the
balloon?
P1v1 = p2v2
V2 = P1V1/P2
= 101.3 X 375/995 = 38.17 cubic cm
4. Daniel popped Raman’s balloon (it accidentally became impailed on a nail). Daniel
promised to buy Raman a new balloon if he can answer the following question. If
sassy Sarah’s silver sphere is originally at 10C, what will be the final temperature
of the ssssphere if the internal pressure is halved?
P1/T1 = P2/T2
P1/283 = P1/2 divided by T2
P1/283 = P1/2T2
2T2 = 283
T2 = 141.5 kelvin
5. Balloons are everywhere. A 95.0C bright blue balloon has a volume of 122cm3. What
volume will the bbballon occupy at -15C?
V1/T1 = V2/T2
122/368 = V2/258
V2 = 122 X 258
368
= 85.53 cubic cm
6.
Claire’s compressed cylinder of awesome oxygen has a volume of 30.0 L and
pressure of 1740 kPa at 27C. Claire wonders wildly about the weather. What is the
temperature of oxygen if curious Claire releases it into a 500.0 L weather balloon at
100.6 kPa?
Ans: V1 = 30 L, P1 = 1740 Kpa, T1 = 27 + 273 =
V2 = 500 L, P2 = 100.6 kpa, T2 =
P1V1/T1 = P2V2/T2
T2 = P2V2T1
P1V1
= 100.6 x 500 x 300
1740 x 30
= 289.08 k
7. Emil is impressed with Claire’s wile weather balloon. Emil emails Claire that he would
like to send his own emissary into the atmosphere. Claire couriers him a stunning,
shiny silver weather balloon with a volume of 500.0 L and tells him to release the
ssswballoon into the atmosphere when the temperature is 16C and the pressure is
100.6 kPa. After 40 minutes, the ssswballoon has risen and is recording a
temperature of -18C and a pressure of 93.5 kPa. What is the volume of Emil’s
ssswballoon at this point?
ANS: V1 = 500 L
V2 =
T1= 16 +273 =
P1 = 100.6 kPA
T2 = -18 +273 =
V2 = T2P1V1
P2T1
V2 = 255 X 100.6kpa X 500
93.5 X 289
P2 = 93.5 KPA
V2 = 474.677 Litre
8. What are the postulates (statements) of the kinetic molecular theory (look back at
chapter 11).
9. What is the difference between real and ideal gases? (look at your assigned reading)
10. A real gas will condense to a liquid when the temperature is low enough. Why doesn’t
this fact support the kinetic molecular theory as it applies to ideal gases?
11. Yen accurately accumulates acetylene gas at 23 C and a total ambient pressure of
98.1 kPa using the water displacement method. What is the partial pressure of dry
acetylene?
12. Ricky realized that the raunchy aroma was the result of the release of 2.600 g of a
volatile organic reagent which contained 0.644 g of carbon and 1.902 g of chlorine.
If the compound contains only carbon, chlorine and hydrogen and occupies 730 mL at
98.7 kPa and 50C. What is the molecular formula of Ricky’s raunchy reagent?
13. Patricia postulated that she could properly compute the molar mass of gas that has
a density of 1.71 g/L at a pressure of 97.0 kPa and a temperature of 26.5C. Help
Patricia complete her computation.
14. Calculate the moles of air in a 250 mL beaker. Explain all of the steps you took to
do this.