Unit 3 Problem Set (GWHS)

Last updated over 2 years ago

20 questions

1

Library

Unit 3 Problem Set (GWHS)

Last updated over 2 years ago

20 questions

Unit 3 Problem Set 
This is just a study guide to help you think about the concepts we covered in this unit, but study guides do not always cover or review everything. Here's some things you can do to prepare for the Unit 3 Exam:

1) Make sure you can explain each of your answers to this Problem Set. Do you understand the concept or did you just memorize arithmetic?
2) Review your Concentration of Dye in Gatorade lab
3) Review your notes. We covered the following topics this unit:
Molarity and Dilutions 
Photoelectric Effect (energy, wavelength, frequency) concepts and calculations 
Spectroscopy (how do molecules interact with different types of radiations/light)
Beer-Lambert Law
Ideal Gas Law (variable relationships and calculations) 
Partial Pressure
Kinetic Molecular Theory (KMT)
Deviation from the Ideal Gas Law
The hardest part of AP exams is that you have to think flexibly. If you truly understand a topic, you can answer a question no matter how it is presented.

1

Unit 3 Problem Set 
This is just a study guide to help you think about the concepts we covered in this unit, but study guides do not always cover or review everything. Here's some things you can do to prepare for the Unit 3 Exam:

1) Make sure you can explain each of your answers to this Problem Set. Do you understand the concept or did you just memorize arithmetic?
2) Review your Concentration of Dye in Gatorade lab
3) Review your notes. We covered the following topics this unit:
Molarity and Dilutions 
Photoelectric Effect (energy, wavelength, frequency) concepts and calculations 
Spectroscopy (how do molecules interact with different types of radiations/light)
Beer-Lambert Law
Ideal Gas Law (variable relationships and calculations) 
Partial Pressure
Kinetic Molecular Theory (KMT)
Deviation from the Ideal Gas Law
The hardest part of AP exams is that you have to think flexibly. If you truly understand a topic, you can answer a question no matter how it is presented.

How many milliliters of 18.2 M H2SO4 are needed to prepare 600.0 mL of 0.10 M H2SO4?

0.30 mL

109 mL

3.3 mL

1.6 mL

What volume of a 0.100M HCl stock solution should be used to prepare 250.00mL of 0.0250M HCl?

1.00 mL 

16.0 mL 

62.5 mL 

100 mL

Which of the following frequencies corresponds to light with the longest wavelength?

3.00 × 1013 s–1

3.20 × 109 s–1

8.50 × 1020 s–1

4.12 × 105 s–1

What is the wavelength of a photon of red light whose frequency is 4.55 × 1014 Hz?

659 m 

6.59 x 10-7 m

1.52 × 10-7 m

152 m

Yellow light can have a wavelength of 5.99x10-7 nm. The energy of a photon of this light is _______ .

1.19 × 10–31 J

5.01 × 1014 J

3.32 × 10–19 J

5.99 × 10–7 J

Food can be heated in a microwave oven when microwave radiation strikes water molecules. Which statement best describes what happens to a water molecule when it is struck by microwave radiation?

The microwave radiation causes electron transitions within water molecules.

The microwave radiation causes vibration of water molecules.

The microwave radiation causes the rotation of water molecules.

The microwave radiation causes electron transitions and vibrations in water molecules.

Carbon dioxide, CO2, is capable of absorbing infrared (IR) radiation and is consider a greenhouse gas. Which statement correctly describes what happens when CO2 absorbs IR radiation?

Electrons in the CO2 molecule absorb energy and transition between energy levels.

The CO2 molecule absorbs energy and vibrates.

The CO2 molecule absorbs energy and rotates.

Electrons in the CO2 molecule absorb energy, causing vibrations and rotations.

Which of the following best explains what happens as photons of visible light are absorbed by dye molecules?

Certain electrons in the dye molecule move to a higher energy level, with the difference in energy between the lower and higher energy levels being the same as the energy of the absorbed photons.

Certain chemical bonds in the dye molecules begin to bend and stretch, with the difference in energy between the lower and higher vibrational states being the same as the energy of the absorbed photons.

The dye molecules begin to rotate faster in certain modes, with the difference in energy between the lower and higher rotational states being the same as the energy of the absorbed photons.

Certain covalent bonds in the dye molecules begin to break and re-form, with the bond energies of the bonds being the same as the energy of the absorbed photons.

The absorption spectrum of a certain red dye is shown above. If a student analyzing the same concentration of this dye neglected to wipe fingerprints off the cuvette before placing it in the spectrophotometer, how would the absorption curve be affected?

The peak of curve would be lower because less light would be absorbed.

The peak of the curve would be higher because more light would be absorbed.

The peak of the curve would be shifted to the left because less light would be absorbed.

The peak of the curve would be shifted to the right because more light would be absorbed.

An experiment was performed to investigate the reaction between Zn metal and Ni2+ ⁡(aq) at different concentrations. Because the Ni2+⁡ (aq) ion is green, the extent of the reaction was determined using spectrophotometric analysis. Four 20.0mL standard solutions of Ni2+ ⁡(aq) were prepared by dissolving NiCl2⋅6⁢ H2⁢O (molar mass 240g/mol) in water. The absorbance of each solution was measured; the results are shown both in the table below and in the following plot of the absorbance data.

What is the expected absorbance of a standard solution made by dissolving 0.0070 mol of NiCl2⋅6⁢H2O in water to make 100.mL of solution?

0.0039 

0.0080

0.045 

0.45

A gaseous air‑fuel mixture in a sealed car engine cylinder has an initial volume of 600 mL at 1.0 atm. To prepare for ignition of the fuel, a piston moves within the cylinder, reducing the volume of the air‑fuel mixture to 50 mL at constant temperature. Assuming ideal behavior, what is the new pressure of the air‑fuel mixture?

About 0.083 atm, because the initial volume of the gas mixture was 12 times larger than its final volume.

About 12 atm, because the volume of the gas mixture decreased by a factor of 12.

About 120. atm, because the initial volume of the gas mixture was 120 times larger than its final volume.

About 550. atm, because the change in the volume of the gas mixture was 550.mL.

At 10.°C, 20.g of oxygen gas exerts a pressure of 2.1atm in a rigid, 7.0L cylinder. Assuming ideal behavior, if the temperature of the gas was raised to 40.°C, which statement indicates the new pressure and explains why?

0.52 atm, because the pressure P decreases by the proportion (10 / 40).

8.4 atm, because the pressure P increases by the proportion (40 / 10).

2.3 atm, because the pressure P increases by the proportion (313 / 283).

1.9 atm, because the pressure P decreases by the proportion (283 / 313).

You fill a balloon with 2.50 moles of gas at 22°C at a pressure of 1.19 atm. What is the volume of the balloon?

3.79 L

11.5 L

50.9 L

72.5 L

A gaseous mixture containing 1.5 mol Ar and 3.5 mol CO2 has a total pressure of 8.6 atm. What is the partial pressure of CO2?

1.6 atm

6.0 atm

8.6 atm

20. atm

Two sealed, rigid 5.0L containers each contain a gas at the same temperature but at a different pressure, as shown above. Also shown are the results of transferring the entire contents of container 1 to container 2. No gases escape during the transfer. Assuming ideal behavior, which statement is correct regarding the total pressure of the gases after they are combined?

The total pressure of the gases in the mixture is the sum of the initial pressures of oxygen gas and nitrogen gas because pressure only depends on the total amount of gas when volume and temperature are held constant.

The total pressure of the gases in the mixture is lower than the sum of the initial pressures of oxygen and nitrogen because some of the energy of the particles will be lost due to an increase in the number of collisions.

The total pressure of the gases in the mixture is higher than the sum of the initial pressures of oxygen and nitrogen because of the intermolecular forces that develop between oxygen and nitrogen molecules.

The total pressure of the gases in the mixture cannot be determined because the actual value of the temperature is not given.

The partial pressures of CH4, N2, and O2 in a sample of gas were found to be 187 mmHg, 487 mmHg, and 555 mmHg, respectively. Calculate the mole fraction of nitrogen.

Note: mmHg (millimeter of mercury) is a unit of pressure. When working with partial pressure problems, the unit of pressure does not need to be in atmospheres (atm).

0.358

0.396

0.451

0.738

Four identical 1.0-L flasks contain the gases He, Cl2, CH4, and NH3, each at 0°C and 1 atm pressure. For which gas do the molecules have the highest average particle speed?

He

Cl2

CH4

NH3

The diagrams above use arrows to represent the speed of a gas particle. Which of the diagrams best represents the speed of the particles of a gas at a fixed temperature, and why?

Diagram 1, because all the particles have the same speed.

Diagram 1, because the particles are moving in different directions.

Diagram 2, because the particles have a net kinetic energy of zero.

Diagram 2, because the particles have a variety of different speeds.

Of the four gases below, which gas would have the largest deviation from ideal behavior?

Note: Attractive forces are more of a factor than volume.

H2

HF

HCl

HBr

The diagrams above represent two samples of Xe gas in containers of equal volume at 280K. Which of the following correctly compares the two samples in terms of their deviation from ideal gas behavior and explains why?

The gas in sample 1 would deviate more from ideal behavior because the average distance an Xe atom travels before colliding with another Xe atom is greater.

The gas in sample 2 would deviate more from ideal behavior because the Xe atoms are closer together, leading to an increase in intermolecular attractions.

The gas in sample 2 would deviate more from ideal behavior because the average speed of the Xe atoms is less, leading to an increase in intermolecular attractions.

The gases in both sample 1 and sample 2 would show the same deviation from ideal behavior.

How many milliliters of 18.2 M H2SO4 are needed to prepare 600.0 mL of 0.10 M H2SO4?

0.30 mL

109 mL

3.3 mL

1.6 mL

What volume of a 0.100M HCl stock solution should be used to prepare 250.00mL of 0.0250M HCl?

1.00 mL 

16.0 mL 

62.5 mL 

100 mL

Which of the following frequencies corresponds to light with the longest wavelength?

3.00 × 1013 s–1

3.20 × 109 s–1

8.50 × 1020 s–1

4.12 × 105 s–1

What is the wavelength of a photon of red light  whose frequency is 4.55 × 1014 Hz?

659 m 

6.59 x 10-7 m

1.52 × 10-7 m

152 m

Yellow light can have a wavelength of 5.99x10-7 nm. The energy of a photon of this light is _______ . 

1.19 × 10–31 J

5.01 × 1014 J

3.32 × 10–19 J

5.99 × 10–7 J

Food can be heated in a microwave oven when microwave radiation strikes water molecules. Which statement best describes what happens to a water molecule when it is struck by microwave radiation?

The microwave radiation causes electron transitions within water molecules.

The microwave radiation causes vibration of water molecules.

The microwave radiation causes the rotation of water molecules.

The microwave radiation causes electron transitions and vibrations in water molecules.

Carbon dioxide, CO2, is capable of absorbing infrared (IR) radiation and is consider a greenhouse gas. Which statement correctly describes what happens when CO2 absorbs IR radiation?

Electrons in the CO2 molecule absorb energy and transition between energy levels.

The CO2 molecule absorbs energy and vibrates.

The CO2 molecule absorbs energy and rotates.

Electrons in the CO2 molecule absorb energy, causing vibrations and rotations.

Which of the following best explains what happens as photons of visible light are absorbed by dye molecules?

Certain electrons in the dye molecule move to a higher energy level, with the difference in energy between the lower and higher energy levels being the same as the energy of the absorbed photons.

Certain chemical bonds in the dye molecules begin to bend and stretch, with the difference in energy between the lower and higher vibrational states being the same as the energy of the absorbed photons.

The dye molecules begin to rotate faster in certain modes, with the difference in energy between the lower and higher rotational states being the same as the energy of the absorbed photons.

Certain covalent bonds in the dye molecules begin to break and re-form, with the bond energies of the bonds being the same as the energy of the absorbed photons.

The absorption spectrum of a certain red dye is shown above. If a student analyzing the same concentration of this dye neglected to wipe fingerprints off the cuvette before placing it in the spectrophotometer, how would the absorption curve be affected?

The peak of curve would be lower because less light would be absorbed.

The peak of the curve would be higher because more light would be absorbed.

The peak of the curve would be shifted to the left because less light would be absorbed.

The peak of the curve would be shifted to the right because more light would be absorbed.

An experiment was performed to investigate the reaction between Zn metal and Ni2+ ⁡(aq) at different concentrations. Because the Ni2+⁡ (aq) ion is green, the extent of the reaction was determined using spectrophotometric analysis. Four 20.0mL standard solutions of Ni2+ ⁡(aq) were prepared by dissolving NiCl2⋅6⁢ H2⁢O (molar mass 240g/mol) in water. The absorbance of each solution was measured; the results are shown both in the table below and in the following plot of the absorbance data.

What is the expected absorbance of a standard solution made by dissolving 0.0070 mol of NiCl2⋅6⁢H2O in water to make 100.mL of solution?

0.0039 

0.0080

0.045 

0.45

A gaseous air‑fuel mixture in a sealed car engine cylinder has an initial volume of 600 mL at 1.0 atm. To prepare for ignition of the fuel, a piston moves within the cylinder, reducing the volume of the air‑fuel mixture to 50 mL at constant temperature. Assuming ideal behavior, what is the new pressure of the air‑fuel mixture?

About 0.083 atm, because the initial volume of the gas mixture was 12 times larger than its final volume.

About 12 atm, because the volume of the gas mixture decreased by a factor of 12.

About 120. atm, because the initial volume of the gas mixture was 120 times larger than its final volume.

About 550. atm, because the change in the volume of the gas mixture was 550.mL.

At 10.°C, 20.g of oxygen gas exerts a pressure of 2.1atm in a rigid, 7.0L cylinder. Assuming ideal behavior, if the temperature of the gas was raised to 40.°C, which statement indicates the new pressure and explains why?

0.52 atm, because the pressure P decreases by the proportion (10 / 40).

8.4 atm, because the pressure P increases by the proportion (40 / 10).

2.3 atm, because the pressure P increases by the proportion (313 / 283).

1.9 atm, because the pressure P decreases by the proportion (283 / 313).

You fill a balloon with 2.50 moles of gas at 22°C at a pressure of 1.19 atm. What is the volume of the balloon?

3.79 L

11.5 L

50.9 L

72.5 L

A gaseous mixture containing 1.5 mol Ar and 3.5 mol CO2 has a total pressure of 8.6 atm. What is the partial pressure of CO2?

1.6 atm

6.0 atm

8.6 atm

20. atm

Two sealed, rigid 5.0L containers each contain a gas at the same temperature but at a different pressure, as shown above. Also shown are the results of transferring the entire contents of container 1 to container 2. No gases escape during the transfer. Assuming ideal behavior, which statement is correct regarding the total pressure of the gases after they are combined?

The total pressure of the gases in the mixture is the sum of the initial pressures of oxygen gas and nitrogen gas because pressure only depends on the total amount of gas when volume and temperature are held constant.

The total pressure of the gases in the mixture is lower than the sum of the initial pressures of oxygen and nitrogen because some of the energy of the particles will be lost due to an increase in the number of collisions.

The total pressure of the gases in the mixture is higher than the sum of the initial pressures of oxygen and nitrogen because of the intermolecular forces that develop between oxygen and nitrogen molecules.

The total pressure of the gases in the mixture cannot be determined because the actual value of the temperature is not given.

The partial pressures of CH4, N2, and O2 in a sample of gas were found to be 187 mmHg, 487 mmHg, and 555 mmHg, respectively. Calculate the mole fraction of nitrogen.

Note: mmHg (millimeter of mercury) is a unit of pressure. When working with partial pressure problems, the unit of pressure does not need to be in atmospheres (atm). 

0.358

0.396

0.451

0.738

Four identical 1.0-L flasks contain the gases He, Cl2, CH4, and NH3, each at 0°C and 1 atm pressure. For which gas do the molecules have the highest average particle speed?

He

Cl2

CH4

NH3

The diagrams above use arrows to represent the speed of a gas particle. Which of the diagrams best represents the speed of the particles of a gas at a fixed temperature, and why?

Diagram 1, because all the particles have the same speed.

Diagram 1, because the particles are moving in different directions.

Diagram 2, because the particles have a net kinetic energy of zero.

Diagram 2, because the particles have a variety of different speeds.

Of the four gases below, which gas would have the largest deviation from ideal behavior?

Note: Attractive forces are more of a factor than volume. 

H2

HF

HCl

HBr

The diagrams above represent two samples of Xe gas in containers of equal volume at 280K. Which of the following correctly compares the two samples in terms of their deviation from ideal gas behavior and explains why?

The gas in sample 1 would deviate more from ideal behavior because the average distance an Xe atom travels before colliding with another Xe atom is greater.

The gas in sample 2 would deviate more from ideal behavior because the Xe atoms are closer together, leading to an increase in intermolecular attractions.

The gas in sample 2 would deviate more from ideal behavior because the average speed of the Xe atoms is less, leading to an increase in intermolecular attractions.

The gases in both sample 1 and sample 2 would show the same deviation from ideal behavior.

Unit 3 Problem Set (GWHS)

Unit 3 Problem Set (GWHS)

Unit 3 Problem Set

Unit 3 Problem Set

How many milliliters of 18.2 M H2SO4 are needed to prepare 600.0 mL of 0.10 M H2SO4?

What volume of a 0.100M HCl stock solution should be used to prepare 250.00mL of 0.0250M HCl?

Which of the following frequencies corresponds to light with the longest wavelength?

What is the wavelength of a photon of red light whose frequency is 4.55 × 1014 Hz?

Yellow light can have a wavelength of 5.99x10-7 nm. The energy of a photon of this light is _______ .

Food can be heated in a microwave oven when microwave radiation strikes water molecules. Which statement best describes what happens to a water molecule when it is struck by microwave radiation?

Carbon dioxide, CO2, is capable of absorbing infrared (IR) radiation and is consider a greenhouse gas. Which statement correctly describes what happens when CO2 absorbs IR radiation?

Which of the following best explains what happens as photons of visible light are absorbed by dye molecules?

The absorption spectrum of a certain red dye is shown above. If a student analyzing the same concentration of this dye neglected to wipe fingerprints off the cuvette before placing it in the spectrophotometer, how would the absorption curve be affected?

At 10.°C, 20.g of oxygen gas exerts a pressure of 2.1atm in a rigid, 7.0L cylinder. Assuming ideal behavior, if the temperature of the gas was raised to 40.°C, which statement indicates the new pressure and explains why?

You fill a balloon with 2.50 moles of gas at 22°C at a pressure of 1.19 atm. What is the volume of the balloon?

A gaseous mixture containing 1.5 mol Ar and 3.5 mol CO2 has a total pressure of 8.6 atm. What is the partial pressure of CO2?

Four identical 1.0-L flasks contain the gases He, Cl2, CH4, and NH3, each at 0°C and 1 atm pressure. For which gas do the molecules have the highest average particle speed?

The diagrams above use arrows to represent the speed of a gas particle. Which of the diagrams best represents the speed of the particles of a gas at a fixed temperature, and why?

Of the four gases below, which gas would have the largest deviation from ideal behavior?Note: Attractive forces are more of a factor than volume.

The diagrams above represent two samples of Xe gas in containers of equal volume at 280K. Which of the following correctly compares the two samples in terms of their deviation from ideal gas behavior and explains why?

Of the four gases below, which gas would have the largest deviation from ideal behavior?

Note: Attractive forces are more of a factor than volume.