Question 1

Which assumption of the Kinetic Molecular Theory is most violated at high pressures?

Accepted Answer

Gas particles have negligible volume compared to the container.

Question 2

Which of the following gases is most likely to behave ideally under standard conditions?

Accepted Answer

H$_2$

Question 3

Why does the van der Waals equation include the term $(V-nb)$?

Accepted Answer

To correct for the volume occupied by gas particles themselves.

Question 4

Which condition would most likely require the pressure correction in the van der Waals equation?

Accepted Answer

Low temperature

Question 5

Given the van der Waals equation $\left(P + a \frac{n^2}{V^2}\right)(V-nb) = nRT$, what does the constant $a$ represent?

Accepted Answer

Magnitude of intermolecular attractive forces

Question 6

A sample of 1.00 mol of CO$_2$ is confined to a 1.00 L container at 300 K. Using the ideal gas law $PV = nRT$, what is the calculated pressure? ($R = 0.0821$ L·atm·mol$^{-1}$·K$^{-1}$)

Accepted Answer

$7.47$ atm

Question 7

Which gas is most likely to exhibit real gas behavior: CH$_4$ or H$_2$O? Why?

Accepted Answer

H$_2$O, because it has strong intermolecular forces.

Question 8

At which condition do gases most closely approach ideal behavior?

Accepted Answer

High temperature and low pressure

Question 9

If the van der Waals constant $b$ for a gas is large, what does this indicate about the gas particles?

Accepted Answer

The gas particles have a large volume.

Question 10

Which of the following best explains why the pressure of a real gas is lower than predicted by the ideal gas law?

Accepted Answer

Attractive forces between gas particles reduce the force of collisions with the container walls.

Question 11

A real gas is compressed to a very small volume. Which correction in the van der Waals equation becomes most significant?

Accepted Answer

Volume correction $(V-nb)$

Question 12

Which of the following statements is true regarding the van der Waals constants for gases?

Accepted Answer

A larger $a$ value indicates stronger intermolecular attractions.

Question 13

Which scenario would most likely cause a gas to deviate from ideal behavior?

Accepted Answer

Low temperature and high pressure

Question 14

If a gas has a very small $a$ and $b$ value, what can you infer about its behavior?

Accepted Answer

It will behave more ideally.

Question 15

Which of the following is a direct consequence of intermolecular attractions in real gases?

Accepted Answer

Measured pressure is lower than predicted by the ideal gas law.

Question 16

A gas sample is cooled to a very low temperature. What effect does this have on its deviation from ideal behavior?

Accepted Answer

Deviation increases due to stronger intermolecular attractions.

Question 17

Which of the following gases would you expect to have the largest van der Waals $a$ constant?

Accepted Answer

H$_2$O

Question 18

Why is the ideal gas law less accurate for gases with strong intermolecular forces?

Accepted Answer

It does not account for attractive forces between particles.

Question 19

Which of the following is NOT an assumption of the Kinetic Molecular Theory?

Accepted Answer

Gas particles exert attractive forces on each other.

Question 20

A sample of gas is found to exert a lower pressure than predicted by the ideal gas law. Which van der Waals constant is most likely responsible for this deviation?

Accepted Answer

a

Real Gases: Deviations from Ideal Gas Behavior and the van der Waals Equation

Study Guide - Practice Questions

Study Guide - Flashcards