f'
"f
MOLAR VOLUME AND
GAS DENSITY
Auogadro's Principle: Equal aolumes of gases contain equal numbers of
molecules at the same temperature and pressur'e
Molar
volume:
one mole of a
gas occupies 22.4
liters at sTp.
1.
2.
What volume in liters will2.7'l moles of He Gas occupy at STp?
6.07
What volume in liters will0.352 moles of carbon monoxide gas occupy at STP?
8.11
3.
A volume of 50.0 dm3 of hy{logen sulfide gas, measured at standard conditions, contains how
many moles of hydrogen sulfide?
2.23
4.
5.
5.
7.
8.
9.
How many moles are in 18.3 liters of HF at STp?
10'
What volume in liters will 100 g of methane gas occupy at STp?
72.
1.3.
24.6
Calculate the mass in grams of 40.0 liters of NO gas at standard conditions.
53.5
How many grarns of nitrogen are there in 100 liters of NO measured at
62.5
STP?
Calculate the mass in grams of
.720liters of carbon dioxide at standard conditions?
235
depity 9f a ggs is expressed units of grams/liter or grams/dm3 or granur dm-3. According to
Avogadr0's h_ypothesis,_1 mole of a gas occupies 22.4 lilers at STP. de mole of a gas is the
gram-moletular mass of the gas (gmw). Theiefdre:
The
This relationship is only for an ideal gas at
1..96
Sl??
What is the density of H2S at STP?
What is the density of oxygen gas at
1,.43
1..52
A volume of 2.00 liters of a gas-, measured at STP, has a mass of. 5.7'1, grams. Calculate the
approximate molecular mass of the gas. Hinh Use the relationship oI D - grams/liter and
D = gmw/?2.4liters.
&.0
14. A volume of
6.82 liters of a ga:, measured at STP, has a mass of 9.15
approximate molecular mass of the gas.
15.
140
What volume, in literq will40.0 g of HCI gas occupy at STp?
Density =
ffi = ffi,
What is the density of COZ at STP?
11.
0.817
g.
Calculate the
30.1
Flask A contains 20.0 liters of CH4 gas. Flask B contains 30.0 liters of CO gas. Each volume is
measured at the same temperature and pressure. If Flask A contains 6.18 miles of CFI4, how
many moles of CO are there in Flask B?
g.Z7
MASS-VOLUME STOICHIOMETRIC PROBLEMS
Volume at STP
1'
7.
How many liters of hydrogen are produced when 2.00
react with an excess of dilute HCI?
g
magnesium ribbon
i.g4
How many liters of oxygen are produced when 1.50 grams of potassium chlorate
are decomposed?
0.411
Hg*
3.
many liters of hydrogen will be produced by the action of 25.0 grams of
calcium metal and an excess of hydrochloric acid? Calcium chloride is the other
product of the reaction.
14.0
4.
To* many Erfms of zinc are needed to produce 5.00 liters of hydrogen when
zinc reacts with an excess of dilute sulfuric
acid?
'
e
U.6
5.
HoY *"1y-qlms of sodium metal are needed to react with an excess of water
to
produce 1.00 liter of hydrogen?
2.05
6.
to produce 50.0 mL of hydrogen?
Tu..y grams of aiuminum are
The aluminum reacts with an excess"Ta99
of dilute iulfuric acid.
7.
chlorine gas-may-be generated in the laboratory by the reaction between
manganese dioxide and. \ydrogen chloride. rie equation is:
Io*
MnOz(s) + 4HCl(a9)
(a) How
MnCtz(aq)
+ 2HzO(l) +
CIZ(g)
-r
many Srams of MnO2 are required to produce 1.00 liter of CIZ at STp?
3.88
6.s1
9]
llo.* ATI grams of HCI are required?
(c) If
the HCI is available as
a watei solution which is 3T.4Vo hydrogen chloride
by mass, and the solution has a specific gravity of 1..189, what n[h-,^" of HCI
solution must be furnished to thl reacti,on?
14.6
B.
9.
What volume of oxygen would be formed by completed. decomposition
I g of mercury(tr) oxide?
of
21.66
7.lz
What volume of chlorine at STP can be obt-11ned by the electrolysis of 100 g
of
sodium chloride in a process that is 807o efficient? Metallic sodium and
chlorine gas are the products of the electrolysis.
15.3
10,
A certain rocket uses butane, c4H10, as fuel. How many kilograms of liquid
oxygen should be carried for the complete combustior oi
kg of tutane
to carbon dioxide and water.vapor? "".h-1.00 o
3.5g
How many liters of oxygen does this represent at STp?
2.51 x 103
7
vf
IDEAL GAS LAW
If R is torr, it's 62.4; chemistry's fun, the other is .0821
T'
IT
RT
rY=
PV = nRT
1.
What pressure will be exerted. by 0.300 mole of gas contained in an 8.00 liters vessel at 18.0'C?
0.81b atm or 681 torr
2.
How many moles of gas will a 486 mL flask hold at 10.0PC and 500 torr?
3.
What is the molecular rrass of a gs if 372 mL have a mass of 0.800 g at 373oC and 800 mm Hg?
0.0138
62.6
4,
What volume witt
5.
A certain gas has a density of 1.34 g/liter at27.0"C and 740 torr. C-alculate the molecular mass of
this gas.
33.9 amu
5.
Sixteen grams of oxygen are introduced into an evacuated 10.0 L flask at
pressure (in atm) in the container?
7.
Ue occupied
by
10.Q
g of nihogen gas at 770 totr apd 27.0"C?
The density of a certain gas at 300 K and 0.974 atmis 2.53
n.}oc.
8.68 L
What is the
g/dnt3. What is its molecular
1.43 atm
mass?
&.0amu