Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Transcript of Atomic Energy
Nuclear radiation was accidentally discovered in 1896 by a French scientist by the name of Henri Becquerel. Becquerel had been performing an experiment in which he hypothesized that fluorescent materials would produce X-rays. He had set up a rig in which a piece of a fluorescent mineral was set on top of a photographic plate; when placed in the Sun, an image of the mineral appeared on the plate. However, during several rainy days, the rig was placed in a drawer; when removed from the drawer, the plate showed an image of the material, showing that the mineral released energy even without light. This release became known as radiation.
Nuclear radiation is produced by a process known as Radioactive Decay.
Nuclear radiation is given off by radioactive nuclei through radioactive decay in three ways: Alpha Decay, Beta Decay, and Gamma Decay. In Alpha Decay, a radioactive nucleus releases alpha particles, or particles with two protons and two neutrons, also known as Helium-4 particles with charges of 2+.
Because of the Law of Conservation of Matter, when a nuclei emits an alpha particle, it leaves behind an atom of the element with 2 less protons and two less neutrons than the starting element.
Basically, in alpha decay, an atom's nucleus releases two protons and two neutrons, creating Helium and another, different element.
One element in which alpha decay occurs is Plutonium-238, which decays to Uranium-234 when it releases an alpha particle. In Beta Decay, a radioactive nucleus releases a beta particle, which can be either a positron or an electron. Both have a near-zero mass, but positrons have a charge of +1, while electrons have a charge of -1.
Two types of beta decay exist: 1) A neutron splits into an electron and a proton, emitting the electron and leaving the nucleus with an extra proton, and 2) A proton splits into a positron and a neutron, emitting the positron and leaving the nucleus with one less proton. As with alpha decay, all matter is conserved in both of these cases.
Basically, in beta decay, an atom releases either a positive positron or a negative electron, losing either a neutron or a proton in the process.
One element in which beta decay occurs is Carbon-11, which decays into Boron-11. Gamma Decay occurs along with beta and alpha decay. During both beta and alpha decay, nucleic particles change positions in order to stabilize their nucleus. When this occurs, energy is released from the radioactive atom as gamma rays, a form of light with an extremely large amount of energy. Gamma rays do not change elements into other elements, as they have no charge or mass.
Basically, energy is released in beta decay and alpha decay. Some of this energy comes in the form of gamma rays. Nuclear Fission occurs when an extremely large, unstable nucleus decays by breaking into two smaller, more stable nuclei, as well as several neutrons. This can happen naturally, or can be induced by bombarding the nucleus with neutrons.
When chemical reactions take place, a small amount of matter is converted into energy. The same applies to nuclear fission. When an atom splits through the process of fission, a tiny amount of matter becomes, and is released as, energy.
When one unstable nuclei undergoes fission, some the neutrons released can collide with nearby atoms, causing them to undergo fission as well. This, in turn, causes the nearby atoms to release even more neutrons, resulting in a nuclear chain reaction - a continuous series of fission reactions.
Basically, when an extremely large, unstable nuclei decays, it does so by splitting into two smaller nuclei, releasing some neutrons and a small amount of energy. The neutrons can sometimes hit other atoms, creating a chain reaction. During a chain reaction caused by fission, massive amounts of energy are released. This energy can be harnessed for human use, with atomic bombs being a clear example.
Fission can also be utilized for electricity generation. Nuclear power plants, which are often less costly and less polluting than fossil fuel plants, provide 20 percent of the United States' electricity. However, because of the limited amount of uranium in the world (which is needed for fission-based power generation), the potential for radioactive explosions (such as the event at Chernobyl, which spread fallout far across Europe), and the fact that they produce long-lasting, highly radioactive waste, nuclear power from fission is seen by many as inefficient and dangerous energy source.
Fusion energy is an option currently being researched by many scientists today. However, despite the fact that there is an abundance of fuel (hydrogen, the element used in fusion, being the most common element in the universe), the tiny amount of waste produced, and the greater safety of fusion reactors, fusion power is currently impractical because the energy needed to produce and contain the hydrogen plasma created in fusion reactions is greater than that released by the fusion. A Presentation by Nick Chechak The End Nuclear Fusion More Information on Radiation Overview of Radiation A visual representation of alpha decay, with a depicting an alpha particle. A visual representation of beta decay, with B representing the beta particle, p representing a proton, and n representing a neutron. A picture representing gamma decay in an atom, with Y representing a gamma ray. Unstable nuclei decay in order to become stable. A nuclei will continue decaying by emitting particles until it becomes a stable atom.
A radioactive isotope's half-life is the amount of time required for half of the isotope's nuclei to decay.
Though all three forms of radiation are able to penetrate matter, some are able to penetrate further than the others. Alpha particles, the largest and most greatly charged, have the least penetrating ability; beta particles, with a lesser charge of +1 or -1 and nearly no mass, have greater penetrating ability. Gamma rays have the greatest penetrating power, with no mass or charge, and are stopped only by dense, thick materials.
Radiation, when absorbed by matter, can break the chemical bonds between atoms. This can damage the cells of living matter (resulting in illnesses), and can even weaken metal, sometimes causing structures to become unsafe.
Scientists can use carbon-14, a radioactive isotope, to determine the age of a once-living organism. All living organisms contain carbon-14, and the level of carbon-14 stays constant during an organism's life, but after death, the amount drops due to carbon-14's decay. Scientists can predict an organism's remains' age by finding how much carbon-14 is left. Unstable nuclei do not always decay through the release of alpha or beta particles or gamma rays. Some decay through the process of Nuclear Fission.
Nuclear Fission is one of the two forms of a subset of atomic energy know as Energy from the Nucleus, in which atomic matter is converted into energy.
The second form of Energy from the Nucleus is a process called Nuclear Fusion, which is, essentially, the opposite of Nuclear Fission. A picture representing fission occurring in a Uranium atom; the neutron, depicted by the small blue circle, collides with the atom to produce U-236, an unstable atom, which proceeds to undergo fission. During Nuclear Fusion, two or more nuclei with low atomic masses overcome the repulsion between themselves and join to form a much more massive nucleus. When this occurs, large amounts of energy are released, along with two beta particles.
The temperatures required to overcome the repulsion between positively charged nuclei are immense - over 1,000,000,000 degrees Centigrade. This is why fusion rarely occurs naturally outside of the cores of stars, such as that of our sun.
Basically, in areas of extremely high temperature, small atoms can overcome their repulsion and fuse to form one big atom, releasing energy and beta particles. An illustration representing nuclear fusion, with Hydrogen-2 and Hydrogen-3 fusing to form Helium-4 and releasing a neutron. An illustration of the penetrating power of each type of radiation, with a depicting Alpha Radiation, B depicting Beta Radiation, and Y depicting Gamma Radiation. The cooling towers of a typical nuclear power plant. This video provides a description and animation of alpha decay. This video provides a description and animation of alpha decay. In this video clip, a team of NASA physicists explain and describe gamma rays. The first half of this news clip details an incident that occurred in Chernobyl, Ukraine, in which nuclear reactor exploded, releasing incredibly harmful radiation into the surrounding areas. This clip is a 3D animation of nuclear fission. This clip is an informational video describing, in detail, how the Sun produces energy through fusion. A clip of a nuclear warhead, powered by fission, being detonated in a Nevada test site.