AP Chemistry Chapter 10 Gases
1. Read pages 343-374 and study the PowerPoint notes.
2. Reread pages 346-348 and then complete problems 13 and 14 on page 376.
3. The following worksheets should be completed as an independent assignment as they are a review of
Year I material: Combined Law, Density at STP, Ideal Gas Equation, Collecting Gases over Water,
Stoichiometry & Gas Volumes, Dalton’s Law of Partial Pressure, and Graham’s Law.
4. The following topics will be discussed in class and then you can complete the corresponding
worksheet: Determining Formulas, Root Mean Square Speed, and Van der Waals Equation.
5. Complete the Sample Multiple Choice Questions.
6. Be sure to visit http://www.collegeboard.com/student/testing/ap/chemistry/samp.html?chem and
review the following Free Response Questions (FRQ): 2009 # 2, 2009 Form B #3a-e, 2006 #3 and 2005
Form B #6. Grade your work using the scoring guides.
7. A 100 point assessment will be given on _________________________________
Equations and Constants given on the AP Exam and on your class test
m V1P1 V2 P2
PV = nRT n K = °C + 273
M =
T1 T2
moles A
PA = Ptotal x XA where = XA Ptotal = PA + PB + PC + …
total moles
r1 M2 3RT
D
m u rms
V r2 M1 M
KE = ½ mv2 KE = 3/2 RT
n 2a
P 2 V nb nRT
V
P = pressure Gas constant, R = 8.314 J mol-1 K-1 = 0.08206 L atm mol-1 K-1
V = volume 1 atm = 760 mm Hg = 760 torr
n = number of mole STP = 0.000°C and 1.000 atm
D = density
m = mass urms = root-mean-square speed
v = velocity KE = kinetic energy
r = rate of effusion
M = molar mass
All other equations and constants used in this chapter must be memorized!!!
See back side for details.
n 2a nRT n 2a
Be able to convert: P
V nb nRT
2
P 2
V to
V nb V
m m
PV = nRT , n , D Know that these formulas can be rearranged to obtain:
M v
mRT mRT DRT PM
PV= M= D=
M PV P RT
Be able to convert the R value given (R = 8.314 J mol-1 K-1) to the R value needed for root-
mean-square speed and KE = 3/2 RT (R = 8,314 g m2 mol-1 K-1 s-2).
(8.314 J mol-1 K-1) x (kg m2 s-2 / J) x (1000g / kg)
Understand that rate (r) and time (t) are inversely proportional and that molar mass (M) and
density (D) are directly proportional so:
r1 t 2 M2 D2
r2 t1 M1 D1
Collecting a Gas over Water Know that:
1. Equal water levels: Pdry gas = Patm - Pwater vapor
2. Unequal water levels: Pdry gas = Patm - Pwater vapor - height of water (mm)
13.5
1.00 atm = 101.3 kPa
DSTP = mass = molar mass molar volume = 22.4 L/mol (only at STP)
volume molar volume