menu
Hit Return to see all results
Chapter 10, Problem 49PS
BuyFindarrow_forward

### Chemistry & Chemical Reactivity

10th Edition
John C. Kotz + 3 others
ISBN: 9781337399074

#### Solutions

Chapter
Section
BuyFindarrow_forward

### Chemistry & Chemical Reactivity

10th Edition
John C. Kotz + 3 others
ISBN: 9781337399074
Textbook Problem

# A gas whose molar mass you wish to know effuses through an opening at a rate one third as fast as that of helium gas. What is the molar mass of the unknown gas?

Interpretation Introduction

Interpretation: The molar mass of the unknown gas should be determined by using the given condition that the gas effuses at one third rate as fast as that of helium gas.

Concept introduction:

Effusion:

The movement of gas particles through a small hole is defined as effusion. The rate of effusion for a gas is inversely proportional to the square root of the mass of gas particles.

The root mean square velocity μ is defined as the measure of velocity of particle in gas. It is the method to determine the single velocity value for particles.

Root mean square velocity can be determined,

μrms=(3RTM)1/2 (1)

(gas constant)R=8.314JKmolM=Molarmass

Molar mass: The molar mass of a substance is determined by dividing the given mass of substance by the amount of the substance.

Explanation

The molar mass of helium gas is 4Â g/mol

Using Grahamâ€™s Law of effusion the molar mass of the unknown gas is calculated as follows,

â€‚Â rateÂ ofÂ unkonwnÂ gasrateÂ ofÂ HeÂ =Â molarÂ massÂ ofÂ HemolarÂ massÂ ofÂ unknown13=4molarÂ massÂ ofÂ unknown4molarÂ massÂ ofÂ unknownâ€Šâ€Š=â€Šâ€Š19molarÂ massÂ ofÂ unknown4â€Šâ€Š=â€Šâ€Š91molarÂ massÂ ofÂ unknownâ€Šâ€Š=â€Šâ€Š9Ã—4â€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Šâ€Š

### Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

#### The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started

## Additional Science Solutions

#### Find more solutions based on key concepts

Show solutions add

#### How is a niche different from a habitat?

Oceanography: An Invitation To Marine Science, Loose-leaf Versin