Ch 10 Homework
Name:
Homework problems are from the Serway & Vuille 10th edition. Follow the instructions and show your
work clearly.
1. (Problem 4)
Death Valley holds the record for the highest recorded temperature in the United States. On July 19,
1913, at a place called Furnace Creek Ranch, the temperature rose to 134 °F. The lowest U.S.
temperature ever recorded occurred at Prospect Creek Camp in Alaska on January 23, 1971, when the
temperature plummeted to -79.8 °F.
(a) Write down the relationship between the Celsius temperature and Fahrenheit temperature.
(b) Convert these temperatures to the Celsius scale.
(c) Convert the Celsius temperatures to Kelvin.
2. (Problem 11)
The New River Gorge Bridge in West Virginia is a 518-m long steel arch. How much will its length change
between temperature extremes of -20°C and 35°C?
(a) Find the coefficient of linear expansion of steel and write down the reference you used.
(b) How much will its length change between temperature extremes of -20°C and 35°C?
3. (Problem 26)
The density of gasoline is
kg/m3 at 0°C. Its average coefficient of volume expansion is
(°C)-1, and note that 1.00 gal = 0.003 80 m3.
(a) Calculate the mass of 10.0 gal of gas at 0°C.
(b) If 1.000 m3 of gasoline at 0°C is warmed by 20.0°C, calculate its new volume.
(c) Using the answer to part (b), calculate the density of gasoline at 20.0°C.
(d) Calculate the mass of 10.0 gal of gas at 20.0°C.
(e) How many extra kilograms of gasoline would you get if you bought 10.0 gal of gasoline at 0°C
rather than at 20.0°C from a pump that is not temperature compensated?
4. (Problem 35)
A weather balloon is designed to expand to a maximum radius of 20.0 m at its working altitude, where
the air pressure is 0.030 atm and the temperature is 200 K. If the balloon is filled at atmosphere
pressure and 300 K, what is its radius at lift off?
(a) Fill out the blanks in the table below
Ground(at lift off)
Working altitude
Pressure(PG)
Pressure(PW)
Temperature(TG)
Temperature(TW)
Volume(VG)
????
Volume(VW)
(b) Using the ideal gas law, determine the volume of the balloon at lift off.
(c) What is its radius at lift off?
5. (Problem 41)
Use Avogadro’s number to find the mass of a helium atom.
(a) What is the molar mass of the helium?
(b) Read Ch10.4 and find the mass of a helium atom.
6. (Problem 43)
At what temperature would the rms speed of helium atoms equal (a) the escape speed from Earth,
m/s and (b) the escape speed from the Moon,
m/s? Note: The mass of a helium
atom value is found in the previous problem.
(a) Read Chapter 7 and find the equation for the escape speed.
(b) Write down the temperature in terms of rms speed, vrms, the mass of a helium, MHe, and
Boltzmann’s constant, KB.
(c) At what temperature would the rms speed of helium atoms equal (a) the escape speed from
Earth?
(d) At what temperature would the rms speed of helium atoms equal (a) the escape speed from the
Moon?
7. (Problem 54)
A vertical cylinder of cross-sectional area A is fitted with a tight-fitting, frictionless piston of mass m
(Figure below).
(a) If n moles of an ideal gas are in the cylinder at a temperature of T, use Newton’s second law for
equilibrium to show that the height h at which the piston is in equilibrium under its own weight
is given by
where P0 is atmosphere pressure. (Hint: Force exerted by the gas (F = (P-
P0) A) must have the same magnitude as the weight of the piston (mg).)
(b) Is the pressure inside the cylinder less than equal to or greater than atmospheric pressure?
(c) If the gas in the cylinder is warmed, how would the answer for h be affected? (Does h increase
or decrease?) Explain your answer.