CHEM 1001/CHM 1020/ Chm1025C/CHM1032C Name:__Answers
Module 5 SamplePretest
Module
Six Part E Gas Law Problems 20 points
Boyle’s
Law see
examples 6.13 & 6.14 p170-171
1. A sample of a gas has a volume of 100 mL when measured at 25 oC
and
760 mmHg. What volume will the gas occupy at 25 oC and 380 mmHg?
V1P1=V2P2
100 mL X 760 mmHg =
200 mL (answer)
1 380
mmHg
Charles
Law see
example 6.15 page 173-174
2. The volume of a
gas is 100.0 mL at 27 oC. At what temperature in degrees Celsius would
the volume of the gas be 200.0 mL, assuming the
pressure remains constant.
V1 = V2 V2
T1__ = T2
T1 T2 V1
200.0 mL x 300 K = 600 K (answer)
100.0 mL
Dalton’s
Law of Partial Pressures
3. The volume of
hydrogen collected over water is 100 mL at 25 oC and 763.8 torre. Calculate the dry volume in milliliters of 200
mL of hydrogen gas collected over water at 25 oC at 760 torre
pressure with the temperature remaining constant. (The partial pressure of water vapor at 25 oC is 23.8 torre.)
Ptotal = PH2
dry + PH2O PH2 dry = 760 torre – 23.8 torre =
736.2 torre
V1P1=V2P2
200 mL
x 736.2 torre =
193.7 mL (Answer)
760 torre
Ideal Gas
Equation-Combined
Gas Laws see example 6.16 page 174-175
5. Calculate the
number of moles of nitrogen gas in a 5.00 L cylinder at 27 oC
and 4 atm pressure. R = 0.0821 L atm/
K mole )
PV = nRT
4 atm x 5.00 L = 0.813 mol
300 K x 0.08205 L atm/Kmol
How much does this
volume of gas weigh?
.813 mol x 28.0 g/mol = 22.8 g
(answer)
Corwin Paper and Pencil
Homework (15 points):
Boyles Law: Questions 15-20 p 306
Charles Law: Questions 21-26 p 306
Combined Gas Law: Questions 33-42 p 306
Dalton’s Law: Questions 47-54 p 306-307
Ideal Gas Behavior and Gas Law: Questions 55-66 p 307