5.3.2 Molar Volume of Gases

• What is the molar volume of a gas defined as?

  Volume of one mole
• The molar volume of a gas is constant for all gases under the same temperature and pressure.
• STP stands for Standard Temperature and Pressure
• What is the temperature and pressure at STP?

  0°C and 1 atm
• What is the temperature at RTP?

  25°C
• The molar volume at STP is 22.4 L/mol.
• Molar volume refers to the space occupied by one mole of a gas.
• What does molar mass refer to?

  Mass of one mole
• What is the Ideal Gas Law equation?

  PV = nRT</latex>
• At constant pressure, molar volume increases as temperature increases.
• What does $R$ in the Ideal Gas Law represent?


  Molar gas constant
• At constant temperature, molar volume decreases as pressure increases.
• What is the molar volume at STP?

  $22.4 \text{ L / mol}$
• The molar volume at RTP is approximately 24.5 \text{ L / mol}</latex>
• What is the value of the molar gas constant $R$?


  8.314 \text{ J / (mol \cdot K)}
• What is the primary difference between molar volume and molar mass?

  Volume versus mass
• The molar volume of a gas is the volume occupied by one mole under specified conditions.
• At STP, the molar volume of a gas is 22.4 L/mol.
• Match the condition with its molar volume:

  STP ↔️ $22.4 \text{ L / mol}$

  RTP ↔️ $24.5 \text{ L / mol}$
• Order the following properties based on their relationship in the Ideal Gas Law:

  1️⃣ Pressure

  2️⃣ Volume

  3️⃣ Number of moles

  4️⃣ Temperature

  5️⃣ Molar gas constant
• How is molar volume calculated using the Ideal Gas Law?

  $V_{m} =$$\frac{RT}{P}$
• At constant pressure, molar volume increases with temperature.
• In the Ideal Gas Law, what is the unit of pressure?

  Pascals (Pa)
• In the Ideal Gas Law, what is the unit of volume?

  Cubic meters (m³)
• Match the property with its symbol:

  Pressure ↔️ $P$

  Volume ↔️ $V$

  Number of moles ↔️ $n$

  Temperature ↔️ $T$
• What does $n$ represent in the ideal gas equation?


  Number of moles
• What is the value of the molar gas constant $R$?


  8.314 \text{ J / (mol \cdot K)}
• The temperature in the ideal gas equation must be in Kelvin
• The ideal gas equation illustrates the relationship between pressure, volume, number of moles, and temperature.
• Match the property with its symbol and standard unit:

  Pressure ↔️ $P$, Pascals (Pa)

  Volume ↔️ $V$, Cubic Meters (m³)

  Number of Moles ↔️ $n$, Moles (mol)

  Temperature ↔️ $T$, Kelvin (K)

  Molar Gas Constant ↔️ $R$, J / (mol \cdot K)
• The ideal gas equation is PV = nRT
• What is the unit of pressure in the ideal gas equation?

  Pascals (Pa)
• What is the unit of volume in the ideal gas equation?

  Cubic Meters (m³)
• The ideal gas equation applies to all gases under any conditions.

  False
• Steps to calculate molar volume using the ideal gas equation:

  1️⃣ Start with the ideal gas equation: $PV =$$nRT$

  2️⃣ Rearrange for molar volume: $V_{m} =$$\frac{V}{n}$

  3️⃣ Substitute $V_{m}$ into the ideal gas equation: $PV_{m} =$$RT$

  4️⃣ Solve for $V_{m}$: $V_{m} =$$\frac{RT}{P}$
• Molar volume depends on temperature and pressure.
• What is the molar volume of an ideal gas at STP?

  $22.4 \text{ L / mol}$
• At RTP, the molar volume of an ideal gas is $24.5 \text{ L / mol}$
• The molar volume of an ideal gas is larger at RTP compared to STP.
• Match the condition with its corresponding temperature, pressure, and molar volume:

  STP ↔️ $273.15 \text{ K}, 101.3 \text{ kPa}, 22.4 \text{ L / mol}$

  RTP ↔️ $298 \text{ K}, 101.3 \text{ kPa}, 24.5 \text{ L / mol}$