Question 1

Which of these is not a possible unit of pressure?

Accepted Answer

lb/s is a unit of mass flow rate, not pressure.

Question 2

A sample of acetylene gas occupies a volume of 47.2 L under a pressure of 1.63 atm at 25 ° C. What will be the volume of the gas if the pressure is decreased to 0.961 atm at 25 ° C?

Accepted Answer

The volume of the gas when the pressure is decreased can be found using Boyle's Law, which states that P1V1 = P2V2 for a given amount of gas at constant temperature. Rearranging this equation to solve for V2 gives V2 = (P1V1)/P2. Substituting the given values (P1 = 1.63 atm, V1 = 47.2 L, P2 = 0.961 atm) into this equation yields V2 = (1.63 atm * 47.2 L) / 0.961 atm = 80.1 L.

Question 3

A balloon contains 14.0 L of air at a pressure of 760 torr. What will be the volume of the air when the balloon is taken to a region with a pressure of 981 torr at constant temperature ?

Accepted Answer

Using the formula P1V1 = P2V2, we can solve for V2:
P1V1 = P2V2
(760 torr)(14.0 L) = (981 torr)(V2)
V2 = (760 torr)(14.0 L) / (981 torr)
V2 = 10.8 L.

Question 4

Which of these statements concerning pressure and weather is/are correct ?
I. Low pressure in a region tends to draw in storms.
II. High pressure in a region usually indicates clear weather.
III. Changes in pressure from region to region are responsible for winds.

Accepted Answer

All three statements are correct. Low pressure areas tend to draw in storms due to the rising warm air, which can lead to cloud formation and precipitation. High pressure areas usually indicate clear weather because the sinking air suppresses cloud formation. Changes in pressure from one region to another drive winds, as air moves from high to low pressure areas.

Question 5

Which of these is not a possible unit of pressure?

Accepted Answer

Pressure is defined as force per unit area. The units for pressure include Pascal (Pa), pounds per square inch (lb/in^2), Newtons per square meter (N/m^2), and millimeters of mercury (mm Hg). Grams per milliliter (g/mL) is a unit of density, not pressure.

Question 6

The layer of air that surrounds the earth is known as the _____.

Accepted Answer

The layer of air that surrounds the earth is known as the atmosphere.

Question 7

For an ideal gas sample, the following graph could represent a plot of  _____.

Accepted Answer

The graph represents a decreasing linear relationship between pressure and volume at a constant temperature, which is consistent with Boyle's law.

Question 8

A sample of  the gas  Freon in an air conditioner has a volume of 325 L and a pressure of 96,300 Pa at 20 ° C. What will be the pressure of Freon when the volume is 975 L at 20 ° C?

Accepted Answer

The answer of A sample of  the gas  Freon in...

Question 9

The unit of pressure is _____.

Accepted Answer

The unit of pressure is force per unit area, and force is measured in Newtons (N) while area is measured in square meters (m²). Therefore, the unit of pressure is N/m². Option D is the only one that matches this unit.

Question 10

Which of these is the correct representation of Charles's law?

Accepted Answer

Charles's law states that at constant pressure, the volume of a gas is directly proportional to its temperature in Kelvin. This can be mathematically represented as V/T=k, where k is a constant.

Question 11

What causes pressure?

Accepted Answer

Pressure is primarily caused by the collisions of gas molecules with their surrounding surfaces, not by their collisions with other gas molecules or changes in temperature.

Question 12

What is the correct conversion factor between atmospheres and torr?

Accepted Answer

The correct conversion factor between atmospheres and torr is 1 atm = 760 torr. This is based on the definition of torr, which is equal to 1/760th of an atmosphere. Therefore, 760 torr is equal to one atmosphere, so option B is correct. Options A, C, D, and E are all incorrect conversion factors between atmospheres and torr.

Question 13

Which of these statements about pressure is /are  incorrect ?
I. Pressure is directly proportional to the number of gas molecules.
II. Pressure is directly proportional to temperature.
III. Pressure is directly proportional to volume.

Accepted Answer

Pressure is inversely proportional to volume according to Boyle's Law, making statement III incorrect.

Question 14

Which of the following is the formula for the chemical compound found in airbags?

Accepted Answer

The chemical compound found in airbags is sodium azide (NaN3), which has the chemical formula of NaN₃. Option B is the closest to this formula, except for a minor typo where there should be a subscript of 1 for nitrogen (N).

Question 15

According to Boyle's law, if the pressure of a gas is increased by a factor of 4, then the _____ of the gas is _____ by a factor of _____.

Accepted Answer

According to Boyle's law, there is an inverse relationship between the pressure and volume of a gas at a constant temperature. This means that as pressure increases, volume decreases, and vice versa. Therefore, if the pressure is increased by a factor of 4, the volume must decrease by a factor of 4 to maintain a constant temperature.

Question 16

A gas cylinder with a movable  piston has a pressure of 100 torr and a volume of 1.0 L. Determine the pressure of the gas if it is compressed to a volume of 0.75 L at constant temperature.

Accepted Answer

According to Boyle's Law, at constant temperature, the pressure and volume of a gas are inversely proportional. This means that as the volume of the gas decreases, the pressure increases.

Using the equation P1V1 = P2V2, where P1 and V1 are the initial pressure and volume, and P2 and V2 are the final pressure and volume:

P1V1 = P2V2

(100 torr)(1.0 L) = P2(0.75 L)

P2 = (100 torr)(1.0 L)/(0.75 L) = 133.33 torr

Therefore, the pressure of the gas when compressed to a volume of 0.75 L is 133.33 torr. The answer is D.

Question 17

Which of these is the correct representation of Boyle's law?

Accepted Answer

Boyle's law states that the pressure of a given mass of gas is inversely proportional to its volume at a constant temperature, which is mathematically represented as PV = k, where P is the pressure, V is the volume, and k is a constant.

Question 18

According to Boyle's law, if the pressure of a gas is decreased by a factor of 5, then the _____ of the gas is _____ by a factor of _____.

Accepted Answer

Boyle's law states that the pressure of a gas is inversely proportional to its volume at constant temperature, meaning if the pressure decreases by a factor of 5, the volume increases by a factor of 5.

Question 19

Which of these is not a possible unit of pressure?

Accepted Answer

J/s (Joule per second) is a unit of power, not pressure. The correct units of pressure are mm Hg (millimeters of mercury), psi (pounds per square inch), torr, and atm (atmospheres).

Question 20

Which of these laws describes the relationship between pressure and volume at a constant temperature?

Accepted Answer

Boyle's law describes the relationship between pressure and volume at a constant temperature, stating that at a constant temperature, the pressure of a fixed amount of gas is inversely proportional to its volume.

Quiz 11: The Air Around Us

Which of these is not a possible unit of pressure?

A sample of acetylene gas occupies a volume of 47.2 L under a pressure of 1.63 atm at 25 ° C. What will be the volume of the gas if the pressure is decreased to 0.961 atm at 25 ° C?

A balloon contains 14.0 L of air at a pressure of 760 torr. What will be the volume of the air when the balloon is taken to a region with a pressure of 981 torr at constant temperature ?

Which of these statements concerning pressure and weather is/are correct ? I. Low pressure in a region tends to draw in storms. II. High pressure in a region usually indicates clear weather. III. Changes in pressure from region to region are responsible for winds.

Which of these is not a possible unit of pressure?

The layer of air that surrounds the earth is known as the _____.

For an ideal gas sample, the following graph could represent a plot of _____.

A sample of the gas Freon in an air conditioner has a volume of 325 L and a pressure of 96,300 Pa at 20 ° C. What will be the pressure of Freon when the volume is 975 L at 20 ° C?

The unit of pressure is _____.

Which of these is the correct representation of Charles's law?

What causes pressure?

What is the correct conversion factor between atmospheres and torr?

Which of these statements about pressure is /are incorrect ? I. Pressure is directly proportional to the number of gas molecules. II. Pressure is directly proportional to temperature. III. Pressure is directly proportional to volume.

Which of the following is the formula for the chemical compound found in airbags?

According to Boyle's law, if the pressure of a gas is increased by a factor of 4, then the ___ of the gas is _ by a factor of ___.

A gas cylinder with a movable piston has a pressure of 100 torr and a volume of 1.0 L. Determine the pressure of the gas if it is compressed to a volume of 0.75 L at constant temperature.

Which of these is the correct representation of Boyle's law?

According to Boyle's law, if the pressure of a gas is decreased by a factor of 5, then the ___ of the gas is _ by a factor of ___.

Which of these is not a possible unit of pressure?

Which of these laws describes the relationship between pressure and volume at a constant temperature?