Question 1

Until recently, materials had to be cooled to temperatures on the order of 4 K to become superconducting. A ceramic has been discovered that becomes superconducting at 92 K. Which of the following temperatures corresponds to 92 K?

Accepted Answer

-181°C is equivalent to 92 K, as the conversion formula from Celsius to Kelvin is $K = °C + 273.15$.

Question 2

At what temperature are the readings on the Celsius and Fahrenheit scales the same? At what temperature are the magnitudes the same but the signs different?

Accepted Answer

-40 °C = -40 °F; -11.4 °C = 11.4 °F

Question 3

What is the melting point of table salt (NaCl) in degrees Fahrenheit, if salt melts at 801°C?

Accepted Answer

To convert 801°C to Fahrenheit, use the formula: (801°C × 9/5) + 32 = 1473.8°F, which rounds to 1474°F.

Question 4

Fahrenheit defined 0° as the lowest temperature that could be achieved by adding salt to ice and found that ice by itself freezes at 32° on this scale. Unfortunately, Fahrenheit's measurements were wrong. The lowest temperature that can be achieved by adding salt to ice is -21.2 °C. Calculate the equivalent temperature on the Fahrenheit scale.

Accepted Answer

The answer of Fahrenheit defined 0° as the lowest temperature...

Question 5

The Kelvin scale is an absolute temperature scale on which one unit, or one Kelvin, is equal to one unit, or one degree, on the Celsius scale. The Rankine scale is an absolute temperature scale on which one unit is equal to one degree on the Fahrenheit scale. Calculate the temperature on the Fahrenheit scale that corresponds to zero on the Rankine scale.

Accepted Answer

The answer of The Kelvin scale is an absolute temperature...

Question 6

Which of the following elements or compounds is most likely to be a gas at room temperature?

Accepted Answer

Chlorine (Cl2) is a nonmetal that exists as a diatomic molecule at room temperature and is a gas under standard conditions.

Question 7

Which of the following relationships between the two variables listed for an ideal gas does $\textbf{       not   }$ give a straight line graph with a positive slope?

Accepted Answer

For an ideal gas, the relationship between pressure (P) and volume (V) at constant temperature is described by Boyle's Law, which states that P is inversely proportional to V. This means that as P increases, V decreases, and vice versa, which does not produce a straight line graph with a positive slope. Instead, it would produce a hyperbolic curve if plotted on a graph of P vs. V.

Question 8

How many cm³ of liquid SO₂ (d = 1.46 g/cm³) can be obtained by compressing 1.00 liter of the gas collected at 25°C and 1 atm?

Accepted Answer

The answer of How many cm³ of liquid SO₂ (d...

Question 9

Three containers of equal volume are filled with three different gases. The first container is filled with Ar, the second with O2 and the third with CO2. The pressure and temperature of the three gases are the same. Which of the following is true of the gases in the three containers?

Accepted Answer

According to the Ideal Gas Law (PV = nRT), where P is pressure, V is volume, n is the number of moles, R is the gas constant, and T is temperature, the number of moles of gas in each container must be the same if the pressure, volume, and temperature are the same. The masses and densities will differ due to the different molar masses of Ar, O2, and CO2.

Question 10

Samples of oxygen and helium have been collected in two separate containers of equal volume. Both gases have the same temperature and pressure. Which of the following statements is true?

Accepted Answer

According to the Ideal Gas Law (PV=nRT), where P is pressure, V is volume, n is the number of moles, R is the gas constant, and T is temperature, the number of moles of gas in each container would be the same if the containers have equal volume, temperature, and pressure, regardless of the gas type.

Question 11

The density of neon gas will be greatest at:

Accepted Answer

The answer of The density of neon gas will be...

Question 12

Calculate the volume in liters occupied by 2.0 g of Ne at 50.0  C and 1.5 atm of pressure.

Accepted Answer

The answer of Calculate the volume in liters occupied by...

Question 13

Ether was one of the first anesthetics discovered. Assume that several mL of ether are placed in a bulb with a volume of 293 mL, and the bulb is immersed in water at 36°C until the last drop of liquid disappears, leaving the bulb filled with ether vapor. The bulb is then removed from the water bath, and the weight of ether that condenses in the bulb is measured. If 0.841 grams of ether collect in this experiment at a pressure of 746 mmHg, what is the molecular weight of ether?

Accepted Answer

The answer of Ether was one of the first anesthetics...

Question 14

Which sample would have the largest volume at 25°C and 750 mmHg?

Accepted Answer

Ammonia (NH3) has the smallest molar mass among the options, resulting in the largest number of moles for a given mass, and thus the largest volume under the same conditions.

Question 15

What is the volume, in liters, of 1.00 mole of an ideal gas at 25.0°C and 1.00 atm pressure?

Accepted Answer

The volume of 1 mole of an ideal gas at standard temperature and pressure (STP, 0°C and 1 atm) is 22.4 L. However, the question specifies 25.0°C (298K), not 0°C. Using the ideal gas law, $PV = nRT$, and solving for $V$ with $P = 1.00 atm$, $n = 1.00 mole$, $R = 0.0821 L·atm/(mol·K)$, and $T = 298K$, gives a volume of approximately 24.5 L.

Question 16

A small gas cylinder of helium used in chemistry lecture demonstrations has a volume of 275 mL at a pressure of 1823 kPa at 24.7°C. Use this information to answer
-The volume of helium, in mL, needed to fill the cylinder at 772 torr and 24.7°C is:

Accepted Answer

Using the ideal gas law and converting units, the volume of helium at 772 torr and 24.7°C is calculated to be approximately 4.87 x 10^3 mL.

Question 17

A small gas cylinder of helium used in chemistry lecture demonstrations has a volume of 275 mL at a pressure of 1823 kPa at 24.7°C. Use this information to answer
-At what temperature in degrees Celsius would the helium gas in the cylinder exhibit a pressure of 25.0 atm?

Accepted Answer

The answer of A small gas cylinder of helium used...

Question 18

A small gas cylinder of helium used in chemistry lecture demonstrations has a volume of 275 mL at a pressure of 1823 kPa at 24.7°C. Use this information to answer
-The number of grams of helium in the cylinder is:

Accepted Answer

The answer of A small gas cylinder of helium used...

Question 19

Polypropylene is a plastic formed by polymerizing propylene, which has the empirical formula CH₂. If a sample of propylene with a mass of 21.0 grams occupies a volume of 11.2 L at STP (0 °C and 1 atm), what is the molecular formula of this gas?

Accepted Answer

At STP, 1 mole of gas occupies 22.4 L. Since 11.2 L is half of 22.4 L, the sample contains 0.5 moles. The molar mass of the sample is 21.0 g / 0.5 mol = 42 g/mol, which corresponds to the molecular formula C₃H₆.

Question 20

A 2.91 gram sample of a gaseous compound that contains only boron and hydrogen has a volume of 1.22 L at 25°C and 1.09 atm. What is the formula of this compound?

Accepted Answer

The answer of A 2.91 gram sample of a gaseous...

Quiz 6: Gases

Until recently, materials had to be cooled to temperatures on the order of 4 K to become superconducting. A ceramic has been discovered that becomes superconducting at 92 K. Which of the following temperatures corresponds to 92 K?

At what temperature are the readings on the Celsius and Fahrenheit scales the same? At what temperature are the magnitudes the same but the signs different?

What is the melting point of table salt (NaCl) in degrees Fahrenheit, if salt melts at 801°C?

Which of the following elements or compounds is most likely to be a gas at room temperature?

Which of the following relationships between the two variables listed for an ideal gas does $\textbf{ not }$ give a straight line graph with a positive slope?

How many cm³ of liquid SO₂ (d = 1.46 g/cm³) can be obtained by compressing 1.00 liter of the gas collected at 25°C and 1 atm?

Three containers of equal volume are filled with three different gases. The first container is filled with Ar, the second with O2 and the third with CO2. The pressure and temperature of the three gases are the same. Which of the following is true of the gases in the three containers?

Samples of oxygen and helium have been collected in two separate containers of equal volume. Both gases have the same temperature and pressure. Which of the following statements is true?

The density of neon gas will be greatest at:

Calculate the volume in liters occupied by 2.0 g of Ne at 50.0 C and 1.5 atm of pressure.

Which sample would have the largest volume at 25°C and 750 mmHg?

What is the volume, in liters, of 1.00 mole of an ideal gas at 25.0°C and 1.00 atm pressure?

A small gas cylinder of helium used in chemistry lecture demonstrations has a volume of 275 mL at a pressure of 1823 kPa at 24.7°C. Use this information to answer -The volume of helium, in mL, needed to fill the cylinder at 772 torr and 24.7°C is:

A small gas cylinder of helium used in chemistry lecture demonstrations has a volume of 275 mL at a pressure of 1823 kPa at 24.7°C. Use this information to answer -At what temperature in degrees Celsius would the helium gas in the cylinder exhibit a pressure of 25.0 atm?

A small gas cylinder of helium used in chemistry lecture demonstrations has a volume of 275 mL at a pressure of 1823 kPa at 24.7°C. Use this information to answer -The number of grams of helium in the cylinder is:

Polypropylene is a plastic formed by polymerizing propylene, which has the empirical formula CH₂. If a sample of propylene with a mass of 21.0 grams occupies a volume of 11.2 L at STP (0 °C and 1 atm) , what is the molecular formula of this gas?

A 2.91 gram sample of a gaseous compound that contains only boron and hydrogen has a volume of 1.22 L at 25°C and 1.09 atm. What is the formula of this compound?

Quiz 6: Gases

Until recently, materials had to be cooled to temperatures on the order of 4 K to become superconducting. A ceramic has been discovered that becomes superconducting at 92 K. Which of the following temperatures corresponds to 92 K?

At what temperature are the readings on the Celsius and Fahrenheit scales the same? At what temperature are the magnitudes the same but the signs different?

What is the melting point of table salt (NaCl) in degrees Fahrenheit, if salt melts at 801°C?

Which of the following elements or compounds is most likely to be a gas at room temperature?

Which of the following relationships between the two variables listed for an ideal gas does not \textbf{ not } not give a straight line graph with a positive slope?

How many cm3 of liquid SO2 (d = 1.46 g/cm3) can be obtained by compressing 1.00 liter of the gas collected at 25°C and 1 atm?

Three containers of equal volume are filled with three different gases. The first container is filled with Ar, the second with O2 and the third with CO2. The pressure and temperature of the three gases are the same. Which of the following is true of the gases in the three containers?

Samples of oxygen and helium have been collected in two separate containers of equal volume. Both gases have the same temperature and pressure. Which of the following statements is true?

The density of neon gas will be greatest at:

Calculate the volume in liters occupied by 2.0 g of Ne at 50.0 C and 1.5 atm of pressure.

Which sample would have the largest volume at 25°C and 750 mmHg?

What is the volume, in liters, of 1.00 mole of an ideal gas at 25.0°C and 1.00 atm pressure?

A small gas cylinder of helium used in chemistry lecture demonstrations has a volume of 275 mL at a pressure of 1823 kPa at 24.7°C. Use this information to answer -The volume of helium, in mL, needed to fill the cylinder at 772 torr and 24.7°C is:

A small gas cylinder of helium used in chemistry lecture demonstrations has a volume of 275 mL at a pressure of 1823 kPa at 24.7°C. Use this information to answer -At what temperature in degrees Celsius would the helium gas in the cylinder exhibit a pressure of 25.0 atm?

A small gas cylinder of helium used in chemistry lecture demonstrations has a volume of 275 mL at a pressure of 1823 kPa at 24.7°C. Use this information to answer -The number of grams of helium in the cylinder is:

Polypropylene is a plastic formed by polymerizing propylene, which has the empirical formula CH2. If a sample of propylene with a mass of 21.0 grams occupies a volume of 11.2 L at STP (0 °C and 1 atm) , what is the molecular formula of this gas?

A 2.91 gram sample of a gaseous compound that contains only boron and hydrogen has a volume of 1.22 L at 25°C and 1.09 atm. What is the formula of this compound?

Which of the following relationships between the two variables listed for an ideal gas does $\textbf{ not }$ give a straight line graph with a positive slope?

How many cm³ of liquid SO₂ (d = 1.46 g/cm³) can be obtained by compressing 1.00 liter of the gas collected at 25°C and 1 atm?

Polypropylene is a plastic formed by polymerizing propylene, which has the empirical formula CH₂. If a sample of propylene with a mass of 21.0 grams occupies a volume of 11.2 L at STP (0 °C and 1 atm) , what is the molecular formula of this gas?