[SOLVED] Physics 230 Homework Set 3

CQ1. You get the flu while traveling in Europe. You measure your temperature and find
that it is 38.7 C. What is your corresponding temperature in K and in F?
(Three significant figures, right?)CQ2. Imagine that you have two identical tanks, one contains nitrogen gas and the other
contains helium gas. Both gases have the same pressure and temperature.
How do the number densities and mass densities compare?CQ3. Imagine a gas in a sealed container. The temperature is doubled and the volume is
tripled.
a) By what factor does the pressure of the gas change?
b) By what factor does the number density of the gas in the container change?CQ4. A gas undergoes an isobaric process where the volume of the gas triples. By what
factor does the gas temperature change?P1. 1.10 moles of gas occupies a volume of 0.0268 m3 at a pressure of 1.15 atm.
a) What is the temperature of the gas in Kelvin?
b) Calculate the number density of the gas.c) Assume that the gas is nitrogen (N2). What is the total mass of the gas and the
mass density of the gas?P2. A car engine contains a cylinder that takes a volume V = 4.65 102 m3 of air into the
cylinders chamber at 32.5C at atmospheric pressure (1.00 atm). The piston then
compresses the air to 1/10 of the original volume and to 25.0 times the original pressure.
Calculate the temperature of this compressed air.P3. Reconsider the cylinder of the previous problem. Assume the cylinder is cylindrical in
shape and has an inner radius that is 1/4 the length of the interior of the cylinder
during the intake of the gas.a) How many moles of gas are contained within the occupied cylinder?
b) Assume that the gas is completely nitrogen (N2). Calculate the mass density of the
gas during the intake and after the compression.P4. A 15.0-cm radius vertical cylinder is sealed at the top by a frictionless 28.0 kg piston.
The piston is 96.0 cm above the bottom when the gas temperature is 350.C. The air
above the piston is at 1.00 atm pressure.a) What is the gas pressure inside the cylinder?
b) What will be the height of the piston if the temperature of the gas is lowered to
35.0C?P5. 0.35 mol of nitrogen gas (N2) is admitted to an evacuated 55 cm3 container at 25C. The
gas then undergoes an isobaric heating to a temperature of 350C.
a) What is the final volume of the gas?
b) Show the process on a pV diagram. Include a proper scale and units on both axes.P6. 7.5 grams of oxygen gas at an initial pressure of 3.5 atm and at 36C undergo an isochoric
process until the pressure has tripled.
a) How many moles of gas does our cylinder contain?
b) What is the new pressure of the gas?
c) What is the gas temperature after this process?The gas volume is then decreased isobarically until the original temperature is reached.
c) What is the volume of the cylinder after the decrease?Finally, the gas is isothermally expanded until it returns to its initial volume.
d) What is the final gas pressure?
e) Show the full three-step process on a pV diagram. Use appropriate scales and units
on both axes.