Chem 101 Exam 3 Flashcards

Which of the following statements correctly describes Boyle's Law?

a. the volume of a gas is directly proportional to the number of moles of the gas, if the pressure and temperature remain constant.

b. the volume of a gas is directly proportional to the Kelvin temperature of the gas, if the pressure and amount of gas remain constant

c. the pressure of gas is inversely proportional to the volume of the gas, if the temperature and amount of gas remain constant

d. the pressure of a gas is directly proportional to the Kelvin temperature of the gas, if the volume and amount of gas remain constant

e. the total pressure exerted by a mixture of gases in a container is the sum of the partial pressures that each gas would exert alone

Dalton's Law of Partial Pressures states which of the following?

a. the total pressure exerted by a mixture of gases in a container is equal to the highest partial pressure exerted by any of the gases in the container

b. the total pressure exerted by a mixture of gases in a container is the sum of the pressures that each gas would exert if present alone under similar conditions

c. the total pressure exerted by a mixture of gases in a container is the average of the pressures that each gas would exert if present alone under similar conditions

d. the total pressure exerted by a mixture of gases in a container is inversely proportional to the pressure that each gas would exert if present alone under similar conditions

e. the total pressure exerted by a mixture of gases in a container is equal to the range of partial pressures of each gas in the container

Two molecules of ethane experience what type of attractive forces?

a. induced dipole - induced dipole interactions

b. dipole-dipole interactions

c. hydrogen bonding

d. ionic bonding

e. covalent bonding

Which of the following is true for a liquid that is placed in a sealed container?

a. evaporation

b. once equilibrium is established between the liquid and the vapor, the rate of the evaporation process will equal the rate of condensation

c. all molecules stay in the liquid state

d. condensation of the evaporated molecules in the jar can only occur once all of the liquid molecules are in the vapor (or gaseous) state

e. a set vapor pressure will be reached, which is the same at all temperatures

What law predicts the expansion of a balloon when helium is added?

a. Boyle's Law

b. Charles's Law

c. Avogadro's Law

d. Ideal Gas Law

e. None of the choices are correct

Which substance is expected to have the highest boiling point?

a. CO₂

b. HCl

c. CH₃OH

d. CH₄

e. BF₃

Which of the following is NOT a unit for measuring pressure?

a. Pa

b. kJ

c. atm

d. mm Hg

e. torr

Which of the following statements conflicts with the kinetic molecular theory of gases?

a. there are no forces between gas particles

b. gas particles occupy a negligible volume compared with the volume of their container

c. the average kinetic energy of the gas particles is proportional to the absolute temperature

d. gas particles lose energy only when they collide with the walls of the container

e. gas particles are in constant, random motion

Which gas under the specified conditions would come closest to exhibiting ideal gas behavior?

a. Cl₂ at low pressure and high temperature

b. PH₃ at low pressure and high temperature

c. Cl₂ at high pressure and low temperature

d. PH₃ at low pressure and low temperature

e. PH₃ at high pressure and low temperature

What is the experimental quantity that serves as a measure of resistance to flow of a liquid?

a. vapor pressure

b. surface tension

c. resistivity

d. viscosity

e. compressibility

Glycerol is a very polar compound. Dimethyl ether is only slightly polar. Which statement is true?

a. glycerol is less viscous than dimethyl ether

b. glycerol will have a greater surface tension than dimethyl ether

c. dimethyl ether has a lower vapor pressure than glycerol

d. the viscosity of both substances will increase with increasing temperatures

e. glycerol will evaporate at a faster rate than dimethyl ether

What is the volume occupied by one mole of helium at 0 Celsius and 1 atm pressure?

a. 1.0 L

b. 22.4 L

c. 4.0 L

d. 40.0 L

e. 12.2 L

What mass of helium is contained in a 2.0 L balloon at 30.0 Celsius and 735 mm Hg?

a. 26.5 g

b. 0.477 g

c. 514 g

d. 66.1 g

e. 0.312 g

A helium filled weather balloon is launched from the ground where the pressure is 752 mm Hg and the temperature is 21 Celsius. Under these conditions its volume is 75.0 L. When it has climbed to an altitude where the pressure is 89 mm Hg and the temperature is 0 Celsius, what is its volume?

a. 0.00 L

b. 8.24 L

c. 9.56 L

d. 588 L

e. 682 L

A gas with pressure of 5.0 atm is compressed at constant temperature from 10.0 L to 2.0 L. What is the pressure of the gas after it is compressed?

a. 4.0 atm

b. 1.0 x 10² atm

c. 1.0 atm

d. 0.40 atm

e. 25 atm

A gas sample is prepared in which the components have the following partial pressures: nitrogen, 555 mm Hg; oxygen, 149 mm Hg; water vapor, 13 mm Hg; argon, 7 mm Hg. What is the total pressure of this mixture?

a. 760 mm Hg

b. 724 mm Hg

c. 1480 mm Hg

d. 386 mm Hg

e. 614 mm Hg

Consider 1.00 L of air in a patient's lungs at 37.0 Celsius and 1.00 atm pressure. What volume would this air occupy if it were at 25.0 Celsius under a pressure of 5.00 x 10² atm?

a. 1.35 x 10^-3 L

b. 480 L

c. 2.08 x 10^-3 L

d. 1.92 x 10^-3 L

e. 374 L

Calculate the density of nitrogen gas (N₂) at STP, in g/L

a. 0.645 g/L

b. 0.800 g/L

c. 1.25 g/L

d. 2.39 g/L

e. 3.58 g/L

A sample of oxygen occupies 1.00 L. If the temperature remains constant, and the pressure on the oxygen is decreased to one third the original pressure, what is the new volume?

a. 3.00 L

b. 1.50 L

c. 0.667 L

d. 0.500 L

e. 0.333 L

A sample of oxygen gas occupies 3.0 L at a pressure of 1.5 atm. If the volume of this sample increases without changing the temperature or the amount of gas, what can be said about the pressure?

a. the pressure of oxygen will remain at 1.5 atm

b. the pressure of oxygen will be less than 1.5 atm

c. the pressure of oxygen will be greater than 1.5 atm

d. the pressure of oxygen will be 4.5 atm

e. it is impossible to predict

A solution contains the label 2.0 M KNO₃. What is the correct interpretation of this concentration?

a. there are 2.0 moles of KNO₃ in 100 mL of water

b. there are 2.0 g of KNO₃ in 100 mL of solution

c. there are 2.0 molecules of KNO₃ in 1 L of solution

d. there are 2.0 moles of KNO₃ in 1 L of water

e. there are 2.0 moles of KNO₃ in 1 L of solution

What type of membrane allows solvent molecules to pass through but do not allow solute molecules to pass through?

a. transport

b. colloidal

c. transparent

d. semipermeable

e. filtering

What happens when a hypotonic solution is separated from a hypertonic solution by an osmotic membrane?

a. water molecules move from the hypotonic solution to the hypertonic solution

b. solute molecules move from the hypertonic solution to the hypotonic solution

c. water molecules move from the hypertonic solution to the hypotonic solution

d. solute molecules move from the hypotonic solution tot he hypertonic solution

e. no net movement of solvent or solute molecules occurs, because the osmotic pressure on both sides is equal

Calculate the concentration (% m/V) of NaCl solution that was made by dissolving 15.0 g of sodium chloride in enough water to make 300.0 mL of solution.

a. 50.0% (m/V)

b. 0.0500% (m/V)

c. 0.356% (m/V)

d. 35.6% (m/V)

e. 5.00% (m/V)

If the concentration of Mg²⁺ in solution is 3.0 x 10^-3 M, what is its concentration expressed in meq/L?

a. 6.0 meq/L

b. 3.0 meq/L

c. 1.5 meq/L

d. 6.0 x 10^-6 meq/L

e. 1.5 x 10^-6 meq/L

Cardiac arrest victims are sometimes treated by injection of a calcium chloride solution directly into the heart muscle. If 2.0 mL of a 5.0% (m/V) CaCl₂ solution is administered to a patient, what mass if CaCl₂ was provided?

a. 1.0 mg

b. 10 mg

c. 0.10 g

d. 10 g

e. 2.5 g