/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 7 (a) Briefly explain the concept ... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 5: Problem 7

(a) Briefly explain the concept of a driving force. (b) What is the driving force for steady-state diffusion?

Short Answer

Expert verified
Answer: The driving force for steady-state diffusion is the concentration gradient, which stays constant during the process. It provides the necessary force for atoms or molecules to move from a region with higher concentration to a region with lower concentration.

Step by step solution

01

(Step 1: Define driving force)

A driving force can be defined as a factor that initiates and sustains a change or process in a system, causing it to move from one state to another. It is essential for understanding various material processes, such as diffusion. In general, the driving force can result from differences in concentration, temperature, or other physical properties across the system.
02

(Step 2: Discuss the concept of diffusion)

Diffusion is a process that occurs in materials where atoms or molecules move from a region with higher concentration to a region with lower concentration, as a result of random thermal motion. The driving force behind diffusion is the difference in concentration (or concentration gradient) between these regions. Diffusion tends to equalize the concentration throughout the material, thus minimizing the concentration differences and reducing the driving force.
03

(Step 3: Explain the concept of steady-state diffusion)

Steady-state diffusion, also known as stationary diffusion, is a specific case of diffusion where the concentration gradient remains constant over time. In steady-state diffusion, the rate at which the particles are moving through the material remains constant. This type of diffusion is often observed when the materials are maintained at a constant temperature and the external conditions remain consistent.
04

(Step 4: Identify the driving force for steady-state diffusion)

The driving force for steady-state diffusion is the concentration gradient, which stays constant during the process. The concentration gradient is the difference in concentration between the regions and provides the necessary force for atoms or molecules to move from the region with higher concentration to the region with lower concentration. In summary, the driving force is a factor that initiates and sustains changes in a system. In the case of steady-state diffusion, the driving force is the concentration gradient, which remains constant during the process.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91影视!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

For the predeposition heat treatment of a semiconducting device, gallium atoms are to be diffused into silicon at a temperature of \(1150^{\circ} \mathrm{C}\) for \(2.5 \mathrm{~h}\). If the required concentration of \(\mathrm{Ga}\) at a position \(2 \mu \mathrm{m}\) below the surface is \(8 \times 10^{23}\) atoms \(/ \mathrm{m}^{3}\), compute the required surface concentration of \(\mathrm{Ga}\). Assume the following: (i) The surface concentration remains constant (ii) The background concentration is \(2 \times 10^{19} \mathrm{Ga}\) atoms \(/ \mathrm{m}^{3}\) (iii) Preexponential and activation energy values are \(3.74 \times 10^{-5} \mathrm{~m}^{2} / \mathrm{s}\) and \(3.39 \mathrm{eV} /\) atom, respectively.

Briefly explain the difference between selfdiffusion and interdiffusion.

An FCC iron-carbon alloy initially containing \(0.55 \mathrm{wt} \% \mathrm{C}\) is exposed to an oxygen-rich and virtually carbon-free atmosphere at \(1325 \mathrm{~K}\) \(\left(1052^{\circ} \mathrm{C}\right)\). Under these circumstances, the carbon diffuses from the alloy and reacts at the surface with the oxygen in the atmosphere-that is, the carbon concentration at the surface position is maintained essentially at \(0 \mathrm{wt} \%\) C. (This process of carbon depletion is termed decarburization.)At what position will the carbon concentration be \(0.25 \mathrm{wt} \%\) after a \(10-\mathrm{h}\) treatment? The value of \(D\) at \(1325 \mathrm{~K}\) is \(3.3 \times 10^{-11} \mathrm{~m}^{2} / \mathrm{s}\).

For a steel alloy, it has been determined that a carburizing heat treatment of \(15 \mathrm{~h}\) duration will raise the carbon concentration to \(0.35 \mathrm{wt} \%\) at a point \(2.0 \mathrm{~mm}\) from the surface. Estimate the time necessary to achieve the same concentration at a 6.0-mm position for an identical steel and at the same carburizing temperature.

(a) Compare interstitial and vacancy atomic mechanisms for diffusion. (b) Cite two reasons why interstitial diffusion is normally more rapid than vacancy diffusion.
See all solutions

Recommended explanations on Physics Textbooks

Astrophysics

Read Explanation

Turning Points in Physics

Read Explanation

Linear Momentum

Read Explanation

Magnetism

Read Explanation

Circular Motion and Gravitation

Read Explanation

Rotational Dynamics

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.