Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 19: Problem 10

A recent study concluded that any amount of radiation exposure can cause biological damage. Explain the differences between the two models of radiation damage, the linear model and the threshold model.

Short Answer

Expert verified
In summary, the linear model of radiation damage assumes that any amount of radiation exposure can cause harm and that damage is directly proportional to the dose received, with no safe level. The threshold model posits that radiation damage only occurs when the dose exceeds a certain threshold, below which the body can repair the harm without any lasting biological impact. Key differences between the two models include the concept of minimum exposure, the relationship between damage and exposure, and the role of biological repair mechanisms in mitigating radiation damage.

Step by step solution

01

Definition of Linear Model

In the linear model, radiation damage is assumed to be directly proportional to the dose received. It suggests that even a small amount of radiation exposure can cause biological harm, with no safe level. This means that increasing the exposure will result in a proportional increase in damage, following a straight line with no lower limit.
02

Definition of Threshold Model

In the threshold model, radiation damage occurs only when the dose exceeds a certain limit called the threshold. Below this threshold, the body can absorb or repair the radiation harm without any lasting biological impact. Above the threshold, damage may increase proportionally or non-linearly with the dose.
03

Key Difference 1: Minimum Exposure

A major difference between the two models is the concept of minimum exposure. In the linear model, even the smallest amount of radiation exposure causes damage, while in the threshold model, no damage is caused below the threshold level.
04

Key Difference 2: Relationship between Damage and Exposure

The relationship between radiation exposure and damage also differs in both models. In the linear model, the relationship is direct and proportional, while in the threshold model, the relationship can be proportional or non-linear after the threshold level is exceeded.
05

Key Difference 3: Biological Repair Mechanism

Another difference lies in the emphasis on the body's ability to repair radiation damage. The threshold model acknowledges the biological capacity to repair damage up to a certain point (the threshold), while the linear model assumes that any amount of radiation exposure will cause irreversible damage. In summary, the key differences between the linear model and the threshold model of radiation damage lie in the minimum exposure required to cause harm, the relationship between the damage and exposure, and the role of the biological repair mechanism.

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

The most significant source of natural radiation is radon- 222 . \({ }^{222} \mathrm{Rn}\), a decay product of \({ }^{238} \mathrm{U}\), is continuously generated in the earth's crust, allowing gaseous \(\mathrm{Rn}\) to seep into the basements of buildings. Because \({ }^{222} \mathrm{Rn}\) is an \(\alpha\) -particle producer with a relatively short half-life of \(3.82\) days, it can cause biological damage when inhaled. a. How many \(\alpha\) particles and \(\beta\) particles are produced when \({ }^{238} \mathrm{U}\) decays to \({ }^{222} \mathrm{Rn}\) ? What nuclei are produced when 222 \(\mathrm{Rn}\) decays? b. Radon is a noble gas so one would expect it to pass through the body quickly. Why is there a concern over inhaling \({ }^{222} \mathrm{Rn}\) ? c. Another problem associated with \({ }^{222} \mathrm{Rn}\) is that the decay of \({ }^{222} \mathrm{Rn}\) produces a more potent \(\alpha\) -particle producer \(\left(t_{1 / 2}=\right.\) \(3.11 \mathrm{~min}\) ) that is a solid. What is the identity of the solid? Give the balanced equation of this species decaying by \(\alpha\) -particle production. Why is the solid a more potent \(\alpha\) -particle producer? d. The U.S. Environmental Protection Agency (EPA) recommends that \({ }^{222} \mathrm{Rn}\) levels not exceed 4 pCi per liter of air \(\left(1 \mathrm{Ci}=1\right.\) curie \(=3.7 \times 10^{10}\) decay events per second; \(\left.1 \mathrm{pCi}=1 \times 10^{-12} \mathrm{Ci}\right) .\) Convert \(4.0 \mathrm{pCi}\) per liter of air into concentrations units of \({ }^{222} \mathrm{Rn}\) atoms per liter of air and moles of \(222 \mathrm{Rn}\) per liter of air.

The radioactive isotope \({ }^{247} \mathrm{Bk}\) decays by a series of \(\alpha\) -particle and \(\beta\) -particle productions, taking \({ }^{247} \mathrm{Bk}\) through many transformations to end up as \({ }^{207} \mathrm{~Pb}\). In the complete decay series, how many \(\alpha\) particles and \(\beta\) particles are produced?

A certain radioactive nuclide has a half-life of \(3.00\) hours. a. Calculate the rate constant in \(\mathrm{s}^{-1}\) for this nuclide. b. Calculate the decay rate in decays/s for \(1.000\) mole of this nuclide.

In each of the following radioactive decay processes, supply the missing particle. a. \({ }^{60} \mathrm{Co} \rightarrow{ }^{60} \mathrm{Ni}+\) ? b. \({ }^{97} \mathrm{Tc}+? \rightarrow{ }^{97} \mathrm{Mo}\) c. \({ }^{99} \mathrm{Tc} \rightarrow{ }^{99} \mathrm{Ru}+\) ? d. \({ }^{239} \mathrm{Pu} \rightarrow{ }^{235} \mathrm{U}+\) ?

One type of commercial smoke detector contains a minute amount of radioactive americium- \(241\left({ }^{241} \mathrm{Am}\right)\), which decays by \(\alpha\) -particle production. The \(\alpha\) particles ionize molecules in the air, allowing it to conduct an electric current. When smoke particles enter, the conductivity of the air is changed and the alarm buzzes. a. Write the equation for the decay of \({ }^{241} \mathrm{Am}\) by \(\alpha\) -particle production. b. The complete decay of \({ }^{241}\) Am involves successively \(\alpha, \alpha\), \(\beta, \alpha, \alpha, \beta, \alpha, \alpha, \alpha, \beta, \alpha\), and \(\beta\) production. What is the final stable nucleus produced in this decay series? c. Identify the 11 intermediate nuclides.
See all solutions

Recommended explanations on Chemistry Textbooks

The Earths Atmosphere

Read Explanation

Nuclear Chemistry

Read Explanation

Making Measurements

Read Explanation

Chemical Reactions

Read Explanation

Physical Chemistry

Read Explanation

Chemistry Branches

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