Radioactivity - PowerPoint PPT Presentation

Loading...

PPT – Radioactivity PowerPoint presentation | free to download - id: 81c56f-MDg1N



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Radioactivity

Description:

Radioactivity Chapter 8 Radioactivity Radioactivity is the emission of alpha, beta or gamma radiation from the nucleus of unstable atoms. It was discovered by ... – PowerPoint PPT presentation

Number of Views:55
Avg rating:3.0/5.0
Slides: 15
Provided by: weeblyCom
Learn more at: http://garballychemistry.weebly.com
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Radioactivity


1
Radioactivity
  • Chapter 8

2
Radioactivity
  • Radioactivity is the emission of alpha, beta or
    gamma radiation from the nucleus of unstable
    atoms.
  • It was discovered by Becquerel, who found that an
    uranium salt had affected a photographic plate.
    Pierre and Mari Curie found two new radioactive
    elements- polonium and radium.
  • .

Becquerel,
3
Pierre and Marie Curie
  • For their work on radioactivity, the Curies were
    awarded the 1903 Nobel Prize in physics. A year
    later, Marie was awarded the Nobel Prize in
    chemistry for her discoveries of radium and
    polonium, thus becoming the first person to
    receive two Nobel Prizes.

Marie Curie ca. 1920. Inset Pierre Curie
(Marie's favorite picture of her husband).
4
Geiger-Muller Tube
  • Radioactive radiation can be detected using a
    Geiger Muller tube

5
Alpha radiation
  • Alpha radiation consists of a stream of
    positively charged particles and so are deflected
    towards the negatively charged plate, and by a
    magnetic field.
  • Alpha particles consists of two protons and two
    neutrons which is the same as the nucleus of
    Helium.
  • The have low penetrating power and are stopped by
    a few centimeters of Air or a sheet of paper.
  • Examples of elements which emit alpha particles
    is americium-241(smoke detectors).

6
(No Transcript)
7
Beta Particles
  • Beta particles are simply electrons. A beta
    particle is formed when a neutron is changed into
    a proton and an electron.
  • They are more penetrating than Alpha particles
    and can penetrate up to 5mm of aluminium.

8
(No Transcript)
9
Gamma radiation
  • Gamma radiation is high energy electromagnetic
    radiation of very short wavelength. It is not
    deflected in electric or magnetic fields. Gamma
    rays have high penetrating ability.
  • Cobalt-60 gives off Gamma radiation. Used to kill
    cancerous cells.

10
(No Transcript)
11
Differences
12
(No Transcript)
13
Half Life
  • The Half-life of an element is the time taken for
    half of the nuclei in any given sample of decay.

http//www.darvill.clara.net/nucrad/types.htm
14
Uses of Radio-isotopes
  • Medicine- Cobalt-60 kill cancer cells
  • Food preservation Gamma rays kill microbes
  • Industry- Tracers added to find source of
    leaking pipes
  • Archeology- Carbon-14 dating by beta
    emmission

15
Radon
About PowerShow.com