Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 18: Problem 7

Define critical mass.

Short Answer

Expert verified
'Critical mass' in nuclear physics is the minimum amount of a substance needed to sustain a nuclear chain reaction. It is the threshold at which a mass can either be 'sub-critical' (not sustaining a chain reaction) or 'super-critical' (sustaining a chain reaction). If a mass is exactly at its critical mass, it is said to be 'critical'.

Step by step solution

01

Understanding 'Critical Mass' in Context

The term 'critical mass' is often encountered in nuclear physics. In this context, it refers to the minimum amount of a substance that is needed to sustain a nuclear chain reaction.
02

Chain Reaction Explanation

In a nuclear chain reaction, an initial reaction causes additional reactions. The critical mass of a substance is the minimum mass that is capable of sustaining a chain reaction. If the mass is below this threshold, it won't be able to sustain a chain reaction. If the mass is above this threshold, it will sustain a chain reaction.
03

Note about 'Sub-critical' or 'Super-critical' Mass

If a mass of substance is below its critical mass, it is called sub-critical. It will not sustain a chain reaction. If a mass of a substance is above its critical mass, it is called super-critical. If it is exactly at its critical mass, it is said to be critical.

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.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

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

Explain why nuclei that emit alpha particles, such as americium-241, are safe to use in smoke detectors.

Research and evaluate environmental issues regarding the storage, containment, and disposal of nuclear wastes.

Why is the constant rate of decay of radioac- tive nuclei so important in radioactive dating?

What type of radiation is emitted in the decay described by the following equation? $$_{19}^{43} \mathrm{K} \rightarrow_{20}^{43} \mathrm{Ca}+?$$

The half-life of cobalt--60 is 10.47 min. How many milligrams of \(\mathrm{Co}-60\) remain after 104.7 min if you start with 10.0 \(\mathrm{mg}\) of \(\mathrm{Co}-60\) ?
See all solutions

Recommended explanations on Chemistry Textbooks

Making Measurements

Read Explanation

Chemical Reactions

Read Explanation

Chemistry Branches

Read Explanation

Inorganic Chemistry

Read Explanation

Organic Chemistry

Read Explanation

Nuclear Chemistry

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.

Sign-up for free