Understanding the Basics of Gas Pressure and Volume

Oct 13, 2025 by wbrum.org 42 views

You Have Four Fixed-Volume Containers at STP: Which Ones Have Equal Pressures?

Understanding the Basics of Gas Pressure and Volume

In chemistry, the behavior of gases is governed by the ideal gas law, which states that the product of the pressure (P) and volume (V) of a gas is equal to the product of the number of moles (n) and the gas constant (R) at a given temperature (T). Mathematically, this is expressed as PV = nRT. At Standard Temperature and Pressure (STP), the temperature is 273.15 K and the pressure is 1 atm.

The Four Containers at STP

We have four fixed-volume containers at STP, each containing a different amount of gas. The details of the containers are as follows:

Container A: 0.5 mol of gas in 11.2 L
Container B: 2 mol of gas in 22.4 L
Container C: 1 mol of gas in 22.4 L
Container D: 3 mol of gas in 44.8 L

Calculating the Pressure in Each Container

To determine which containers have equal pressures, we need to calculate the pressure in each container using the ideal gas law. We can rearrange the ideal gas law to solve for pressure: P = nRT / V.

Container A

For Container A, we have:

n = 0.5 mol V = 11.2 L R = 0.0821 L atm/mol K (gas constant at STP) T = 273.15 K

P = nRT / V = (0.5 mol) (0.0821 L atm/mol K) (273.15 K) / (11.2 L) = 1.07 atm

Container B

For Container B, we have:

n = 2 mol V = 22.4 L R = 0.0821 L atm/mol K (gas constant at STP) T = 273.15 K

P = nRT / V = (2 mol) (0.0821 L atm/mol K) (273.15 K) / (22.4 L) = 2.14 atm

Container C

For Container C, we have:

n = 1 mol V = 22.4 L R = 0.0821 L atm/mol K (gas constant at STP) T = 273.15 K

P = nRT / V = (1 mol) (0.0821 L atm/mol K) (273.15 K) / (22.4 L) = 1.07 atm

Container D

For Container D, we have:

n = 3 mol V = 44.8 L R = 0.0821 L atm/mol K (gas constant at STP) T = 273.15 K

P = nRT / V = (3 mol) (0.0821 L atm/mol K) (273.15 K) / (44.8 L) = 1.07 atm

Which Containers Have Equal Pressures?

From the calculations above, we can see that Container A, Container C, and Container D have equal pressures, which is 1.07 atm. This is because they have the same number of moles of gas per unit volume, which is a key factor in determining the pressure of a gas.

Conclusion

In conclusion, the containers with equal pressures are Container A, Container C, and Container D. This is because they have the same number of moles of gas per unit volume, which is a key factor in determining the pressure of a gas. The ideal gas law is a powerful tool for understanding the behavior of gases, and it can be used to calculate the pressure of a gas in a given container.

Key Takeaways

The ideal gas law is a fundamental concept in chemistry that describes the behavior of gases.
The pressure of a gas is determined by the number of moles of gas per unit volume.
Containers with the same number of moles of gas per unit volume will have equal pressures.
The gas constant (R) is a key factor in determining the pressure of a gas.

Further Reading

Ideal gas law: PV = nRT
Gas constant (R): 0.0821 L atm/mol K (at STP)
Standard Temperature and Pressure (STP): 273.15 K and 1 atm.
You Have Four Fixed-Volume Containers at STP: Which Ones Have Equal Pressures? - Q&A

Understanding the Basics of Gas Pressure and Volume

In our previous article, we discussed the behavior of gases in four fixed-volume containers at Standard Temperature and Pressure (STP). We calculated the pressure in each container using the ideal gas law and found that Container A, Container C, and Container D have equal pressures.

Q&A Session

We received many questions from our readers regarding the behavior of gases in these containers. Here are some of the most frequently asked questions and our answers:

Q: Why do Container A, Container C, and Container D have equal pressures?

A: Container A, Container C, and Container D have equal pressures because they have the same number of moles of gas per unit volume. This is a key factor in determining the pressure of a gas.

Q: What is the ideal gas law?

A: The ideal gas law is a fundamental concept in chemistry that describes the behavior of gases. It states that the product of the pressure (P) and volume (V) of a gas is equal to the product of the number of moles (n) and the gas constant (R) at a given temperature (T). Mathematically, this is expressed as PV = nRT.

Q: What is the gas constant (R)?

A: The gas constant (R) is a key factor in determining the pressure of a gas. It is a constant that relates the pressure and volume of a gas to the number of moles and temperature. At STP, the gas constant is 0.0821 L atm/mol K.

Q: What is Standard Temperature and Pressure (STP)?

A: Standard Temperature and Pressure (STP) is a set of conditions that are used as a reference point for measuring the properties of gases. At STP, the temperature is 273.15 K and the pressure is 1 atm.

Q: How can I calculate the pressure of a gas in a given container?

A: To calculate the pressure of a gas in a given container, you can use the ideal gas law. Rearrange the equation to solve for pressure: P = nRT / V.

Q: What are some common applications of the ideal gas law?

A: The ideal gas law has many practical applications in chemistry and engineering. Some common applications include:

Calculating the pressure of a gas in a container
Determining the volume of a gas at a given pressure and temperature
Calculating the number of moles of a gas in a container
Understanding the behavior of gases in different conditions

Q: What are some common mistakes to avoid when using the ideal gas law?

A: Some common mistakes to avoid when using the ideal gas law include:

Not using the correct units for the variables
Not accounting for the temperature and pressure of the gas
Not using the correct value for the gas constant (R)
Not considering the behavior of real gases, which may not follow the ideal gas law

Conclusion

In conclusion, the ideal gas law is a powerful tool for understanding the behavior of gases. By using the ideal gas law, we can calculate the pressure of a gas in a given container and determine the number of moles of a gas in a container. We hope this Q&A article has been helpful in answering some of the most frequently asked questions about the ideal gas law.

Key Takeaways

The ideal gas law is a fundamental concept in chemistry that describes the behavior of gases.
The pressure of a gas is determined by the number of moles of gas per unit volume.
Containers with the same number of moles of gas per unit volume will have equal pressures.
The gas constant (R) is a key factor in determining the pressure of a gas.
Standard Temperature and Pressure (STP) is a set of conditions that are used as a reference point for measuring the properties of gases.

Further Reading

Ideal gas law: PV = nRT
Gas constant (R): 0.0821 L atm/mol K (at STP)
Standard Temperature and Pressure (STP): 273.15 K and 1 atm
Real gases: gases that do not follow the ideal gas law.