Discovery of Atom (PPT form)

1. By Jennifer Kim
Discovery of the Atoms

2. Rutherford
• Rutherford was a New Zealand scientist, he discovered the structure of the atom with Niel Bohr. It is
known as the Rutherford-Bohr Theory of Atomic Structure.
• One of his experiment was, which he shot relatively large, charged particles called the “Alpha
particles” at a thin gold foil. Through this project Rutherford concluded that each atom was mostly
empty space with dense region (central mass) in positive charge.
• However, he made an serious flaw that electrons needed to orbit, but his analysis of energy were
made when an electron dropped from a higher energy orbit to a lower energy orbit. So, he wasn’t
able to get the best result out of his experiment of understanding the atom.

3. Who is Niels Bohr?
• Niels Bohr focused on researching the structure of the atom, and completed
the structure at 1913.
• Niels Bohr introduced the theory of electrons traveling around the atom’s
nucleus, electron moves to a higher orbit with larger radius, absorbing the
radiation. Bohr’s atomic
models form World
• He also described the Periodic Table, and that nucleus as a compound Book Encyclopedia
structure. (1999 edition)
• During his time for understanding how to make Atomic bomb, he was
disturbed by escaping the invasion of Nazis in the World War II. His family
was half Jew, and escaped to Denmark then Sweden.

4. J J Thomson
• J J Thomson is scientist from England, who were honored for researching the discharge of
electricity in gases.
• He made many important experiments on electromagnetism and atomic particles, such as
creating the “cathode ray tube.” It is a vacuum tube containing electron gun with the source of
electrons. This is the move and deflect the electron beam in order to show images in form of
light.
• His experiment creation were made with simpler materials and bad quality, which gave him
struggles to understand the result. The days back then, didn’t have the developed technology as
it is today. So the materials were a little in-functional.

5. John Dalton
John Dalton's Original Table of Atomic
Weights
• John Dalton was a scientist who worked and focused on the behavior and properties
of gases.
• John Dalton worked on experiments which proved that the understandings of gas
and the elements were used to find out the atomic weight of each element.
• John Dalton’s performed experiments were well done, but he did not know about
their structure. Which he knew his result will be something fundamental.

6. Democritus
• He was a philosopher. Philosophers are people who think about the world, including the atoms. However, he studied many
things other than atoms. Such as, animals, plants, weather, and stars.
• He found that there were infinite number of different types of atoms. They were kinds of shape and size which were made
from the same stuff. So how the substance was solid or liquid, hot or cold, spicy or sweet, he thought they were all because
of the appearance of atoms.
• However, his limitation was that he didn’t do any experiments or have the equipments to. He didn’t have the special
microscope to see the atoms, so he had to invent with his own imaginations. It was also too old back then, which was
harder to discover new things on their own.

7. Global Issue of Atoms
• Electricity from: Nuclear Power “Are they really necessary?”
• These nuclear power plants are fueled by uranium, this naturally occurs in
the Rocky Mountains, countries such as Canada, Australia, and South Africa.
• The nuclear reaction generates heat to generate electricity, which is like fossil
fuels; it is an finite non-renewable resource.
• We need them for radioactive materials, for treatments in medicine,
radiography, to remote locations, space applications, and finally for food
irradiation.
• Their air emissions are not similar of those fossil plants, but they release small
amounts of airborne radioactive gasses.
• So does the nuclear plants that works upon water, it will impact water
resources
• The radioactive wastes from the nuclear power, risks health and will be
stored for centuries.

8. Environment and Economic
The most recent issues from today, Nuclear power can bring out
“Chernobyl.” It is when the radiation levels are every where elevating
normally from 10 to 100. It can also harm the water for the coolings
systems of the plants, and produce radioactive wastes.
Japan’s • The cost of building a nuclear power plants is an
Nuclear expensive project, the long planning and building
will invariably cost a lot.
Radiation • Also, the after cost of this project will be huge.
“Imagine” the cost involved with storing nuclear
waste for thousands of years. How much will that be?

9. • Works Cited
"Chernobyl Legacy Lingers in Britain." Green Living Tips - a More
Environmentally Friendly Life. Web. 03 Nov. 2011. <http://
www.greenlivingtips.com/blogs/389/Chernobyl-legacy-lingers-in-
Britain.html>.
"Electricity from Nuclear Power." Power Scorecard Homepage.
Web. 03 Nov. 2011. <http://www.powerscorecard.org/
tech_detail.cfm?resource_id=7>.
"History of Atoms." NoBeliefs.com (Freethinkers). Web. 03 Nov.
2011. <http://nobeliefs.com/atom.htm>.
"J. J. Thomson's Cathode Ray Experiment." The Scientific Method,
Science, Research and Experiments. Web. 03 Nov. 2011. <http://
www.experiment-resources.com/cathode-ray.html>.

10. "John Dalton’s Atomic Theory." Universe Today — Space and
Astronomy News. Web. 03 Nov. 2011. <http://
www.universetoday.com/38193/john-daltons-atomic-theory/>.
"Nuclear Energy | Clean Energy | US EPA." US Environmental
Protection Agency. Web. 03 Nov. 2011. <http://www.epa.gov/
cleanenergy/energy-and-you/affect/nuclear.html>.
"Rutherford-Bohr Model | Radiation Protection | US EPA." US
Environmental Protection Agency. Web. 03 Nov. 2011. <http://
www.epa.gov/radiation/understand/rutherford.html>.
Book Source:
Pasachoff, Naomi. Niels Bohr Physicist and Humanitarian.
United States of America: Enslow, 2003. Print. Great Minds of
Science.