Problems A
169
swept out through the capillary, and the excess liquid has boiled away, leaving the flask filled only with the vapor of the liquid At this point the flask is
removed from the boiling water and cooled The vapor condenses to liquid,
and air rushes in to fill the flask again Whereas the flask, when emptv and
dry, weighed 453201 g, after the experiment it weighs 460513 g The
barometric pressure during the experiment is 735 torr The volume of the flask
is determined by filling the flask with water, inserting the stopper to its previ
ous position, and squeezing out the excess water through the capillary The
volume of water so held is 263 2 ml What is the mole weight of the liquid '
26 The liquid used in Problem 25 is analyzed and found to be 54 5% C, 9 10% H,
and 36 4% O What is the true molecular formula of this liquid'
27 An automobile tire has a gauge pressure of 32 lb/m
2 at 20°C when the prevailing atmospheric pressure is 14 7 lb/m
2 What is the gauge pressure if the
temperature rises to 50°C
9
28 It takes 1 mm and 37 sec for a given volume of chlorine (CIJ to effuse through
a pinhole under given conditions of temperature and pressure How long will it
take for the same volume of water vapor to effuse through the same hole
under the same conditions'
7
29 Argon effuses through a hole (under prescribed conditions of temperature and
pressure) at the rate of 3 0 ml/mm At what velocity will xenon effuse through
the same hole under the same conditions
9
30 A rubber balloon weighing 5 0 g is 12 inches in diameter when filled with
hydrogen at 730 torr and 25°C How much will the balloon lift in addition to its
own weight
1 (Assume the density of air to be 12 g/hter under these conditions )
31 (a) If the balloon of Problem 30 were filled with ammonia gas (NH,) under the
same conditions, would it rise
1
(b) If so, how much weight would it lift
11
32 What must be the composition of a mixture of H 2 and O 2 if it inflates a balloon
to a diameter of 15 inches and yet the balloon /us! bauh rises from a table
top
7 (The balloon weighs 6 0 g, and the pressure and temperature are 740 torr
and 30°C )
33 Oxygen is commonly sold in 6 0 ft' steel cylinders at a pressure of 2000 lb/m
j
(at 70°F) What weight of oxygen does such a cylinder contain' (Assume
oxygen to be an ideal gas under these conditions )
34 The average breath that an 18-year old takes when not exercising is about 300
ml at 20°C and 750 torr His respiratory rate is about 20 breaths/mm
(a) What volume of air, corrected to standard conditions, does an average
18-year-old breathe each day'
(b) What weight of air does he breathe each day
7 (Assume that air is 21%
oxygen and 79% nitrogen by volume )
35 The percentage of CO 2 in normal air is 0 035% by volume, and that in the
exhaled air of the average 18-year-old is about 4 0%
169
swept out through the capillary, and the excess liquid has boiled away, leaving the flask filled only with the vapor of the liquid At this point the flask is
removed from the boiling water and cooled The vapor condenses to liquid,
and air rushes in to fill the flask again Whereas the flask, when emptv and
dry, weighed 453201 g, after the experiment it weighs 460513 g The
barometric pressure during the experiment is 735 torr The volume of the flask
is determined by filling the flask with water, inserting the stopper to its previ
ous position, and squeezing out the excess water through the capillary The
volume of water so held is 263 2 ml What is the mole weight of the liquid '
26 The liquid used in Problem 25 is analyzed and found to be 54 5% C, 9 10% H,
and 36 4% O What is the true molecular formula of this liquid'
27 An automobile tire has a gauge pressure of 32 lb/m
2 at 20°C when the prevailing atmospheric pressure is 14 7 lb/m
2 What is the gauge pressure if the
temperature rises to 50°C
9
28 It takes 1 mm and 37 sec for a given volume of chlorine (CIJ to effuse through
a pinhole under given conditions of temperature and pressure How long will it
take for the same volume of water vapor to effuse through the same hole
under the same conditions'
7
29 Argon effuses through a hole (under prescribed conditions of temperature and
pressure) at the rate of 3 0 ml/mm At what velocity will xenon effuse through
the same hole under the same conditions
9
30 A rubber balloon weighing 5 0 g is 12 inches in diameter when filled with
hydrogen at 730 torr and 25°C How much will the balloon lift in addition to its
own weight
1 (Assume the density of air to be 12 g/hter under these conditions )
31 (a) If the balloon of Problem 30 were filled with ammonia gas (NH,) under the
same conditions, would it rise
1
(b) If so, how much weight would it lift
11
32 What must be the composition of a mixture of H 2 and O 2 if it inflates a balloon
to a diameter of 15 inches and yet the balloon /us! bauh rises from a table
top
7 (The balloon weighs 6 0 g, and the pressure and temperature are 740 torr
and 30°C )
33 Oxygen is commonly sold in 6 0 ft' steel cylinders at a pressure of 2000 lb/m
j
(at 70°F) What weight of oxygen does such a cylinder contain' (Assume
oxygen to be an ideal gas under these conditions )
34 The average breath that an 18-year old takes when not exercising is about 300
ml at 20°C and 750 torr His respiratory rate is about 20 breaths/mm
(a) What volume of air, corrected to standard conditions, does an average
18-year-old breathe each day'
(b) What weight of air does he breathe each day
7 (Assume that air is 21%
oxygen and 79% nitrogen by volume )
35 The percentage of CO 2 in normal air is 0 035% by volume, and that in the
exhaled air of the average 18-year-old is about 4 0%