The average kinetic energy of the molecules in a gas sample depends only on the temperature, T. However, given the same kinetic energies, a lighter molecule will move faster than a heavier molecule, as shown in the equation for rms speed rms speed = rms speed: 3RT where R = 8.314 J/(mol·K) and M is molar mass in kilograms per mole. Note that a joule is the same as a kilogram-meter squared per second squared (kg-m²/s²). What is the rms speed of N₂ molecules at 497 K? V M rms speed: What is the rms speed of He atoms at 497 K? m/s m/s

Chemistry
10th Edition
ISBN:9781305957404
Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Chapter1: Chemical Foundations
Section: Chapter Questions
Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...
icon
Related questions
icon
Concept explainers
Question
**Understanding the Root Mean Square (RMS) Speed of Gas Molecules**

The average kinetic energy of the molecules in a gas sample depends solely on the temperature, \( T \). However, given the same kinetic energies, a lighter molecule will move faster than a heavier molecule. This concept is illustrated by the equation for RMS speed:

\[
\text{rms speed} = \sqrt{\frac{3RT}{\mathcal{M}}}
\]

Here, \( R = 8.314 \, \text{J/(mol} \cdot \text{K)} \) is the gas constant, and \( \mathcal{M} \) is the molar mass in kilograms per mole. It's important to note that a joule is equivalent to a kilogram-meter squared per second squared (kg·m\(^2\)/s\(^2\)).

### Examples:

1. **What is the RMS speed of \(\text{N}_2\) molecules at 497 K?**

   \(\text{rms speed:} \) [ _________ ] m/s

2. **What is the RMS speed of He atoms at 497 K?**

   \(\text{rms speed:} \) [ _________ ] m/s

By using this formula, you can calculate the RMS speed for different gases at a specific temperature, understanding how mass and temperature affect molecular speed.
Transcribed Image Text:**Understanding the Root Mean Square (RMS) Speed of Gas Molecules** The average kinetic energy of the molecules in a gas sample depends solely on the temperature, \( T \). However, given the same kinetic energies, a lighter molecule will move faster than a heavier molecule. This concept is illustrated by the equation for RMS speed: \[ \text{rms speed} = \sqrt{\frac{3RT}{\mathcal{M}}} \] Here, \( R = 8.314 \, \text{J/(mol} \cdot \text{K)} \) is the gas constant, and \( \mathcal{M} \) is the molar mass in kilograms per mole. It's important to note that a joule is equivalent to a kilogram-meter squared per second squared (kg·m\(^2\)/s\(^2\)). ### Examples: 1. **What is the RMS speed of \(\text{N}_2\) molecules at 497 K?** \(\text{rms speed:} \) [ _________ ] m/s 2. **What is the RMS speed of He atoms at 497 K?** \(\text{rms speed:} \) [ _________ ] m/s By using this formula, you can calculate the RMS speed for different gases at a specific temperature, understanding how mass and temperature affect molecular speed.
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps with 2 images

Blurred answer
Knowledge Booster
Thermochemistry
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.
Similar questions
  • SEE MORE QUESTIONS
Recommended textbooks for you
Chemistry
Chemistry
Chemistry
ISBN:
9781305957404
Author:
Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:
Cengage Learning
Chemistry
Chemistry
Chemistry
ISBN:
9781259911156
Author:
Raymond Chang Dr., Jason Overby Professor
Publisher:
McGraw-Hill Education
Principles of Instrumental Analysis
Principles of Instrumental Analysis
Chemistry
ISBN:
9781305577213
Author:
Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:
Cengage Learning
Organic Chemistry
Organic Chemistry
Chemistry
ISBN:
9780078021558
Author:
Janice Gorzynski Smith Dr.
Publisher:
McGraw-Hill Education
Chemistry: Principles and Reactions
Chemistry: Principles and Reactions
Chemistry
ISBN:
9781305079373
Author:
William L. Masterton, Cecile N. Hurley
Publisher:
Cengage Learning
Elementary Principles of Chemical Processes, Bind…
Elementary Principles of Chemical Processes, Bind…
Chemistry
ISBN:
9781118431221
Author:
Richard M. Felder, Ronald W. Rousseau, Lisa G. Bullard
Publisher:
WILEY