CHEM 111 USF Chem Questions

CHEM 111Homework – Ch. 10
due in class Fri 12/2
Name _______________________________________
Questions are worth 4 points each.
1. Hemoglobin is the protein that transports O2 through the blood from the lungs to the rest of the body.
In doing so, each molecule of hemoglobin combines with four molecules of O2. If 1.00 g of
hemoglobin combines with 1.53 mL of O2 at 37°C and 743 torr, what is the molar mass of
hemoglobin?
2. Applications of the ideal gas law:
a. The density of a noble gas is 2.71 g/L at 3.00 atm and 0°C. Identify the gas.
b. A 0.482-g sample of liquid hydrocarbon known to consist of molecules with five carbon
atoms is vaporized in a 0.204-L flask by immersion in a water bath at 101°C. The barometric
pressure is 767 torr. What is the molecular formula of the hydrocarbon?
3. Non-ideal gas behavior:
a. Do intermolecular attractions cause negative or positive deviations from the PV/RT ratio of an
ideal gas? Use data from Table 10.2 in your book to rank CO2, N2, and He in order of
increasing magnitude of these deviations. Briefly explain your answer.
b. Does molecular size cause negative or positive deviations from the PV/RT ratio of an ideal
gas? Use data from Table 10.2 to rank Cl2, H2, and O2 in order of increasing magnitude of
these deviations. Briefly explain your answer.
4. Radon (Rn) is the heaviest, and only radioactive, member of Group 8A(18), the noble gases. It is a
product of the disintegration of heavier radioactive nuclei, such as radium (Ra), found in minute
concentrations in many common rocks used for building and construction. In recent years, health
concerns about the cancers caused from inhaled residential radon have grown. If 1.0´1015 atoms of Ra
produce an average of 1.373´104 atoms of Rn per second, how many liters of Rn, measured at STP,
are produced per day by 1.0 g of Ra?
5. (Challenge question) A person inhales air richer in O2 and exhales air richer in CO2 and water vapor.
During each hour of sleep, a person exhales a total of about 300 L of this CO2- and H2O-enriched air.
a. If the partial pressures of CO2 and H2O in exhaled air are each 30.0 torr at 37.0°C, calculate
the masses of CO2 and H2O exhaled in 1 h of sleep.
b. How many grams of body mass does the person lose in an 8-hour sleep if all of the CO2 and
H2O exhaled come from the metabolism of glucose?
C6H12O6 (s) + 6 O2 (g) ® 6 CO2 (g) + 6 H2O (g)