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For a chain reaction occur each fission must produce at least ____more fission reaction?
you know know you
its 1 i think
Lemon Lime
Anonymous
1::::: APEX (I Just took the test)
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What is a fission nuclear reaction?
The primary result of a fission reaction is the conversion of mass to energy. In fission, the nucleus split, either through radioactive decay or as result of being bombarded by other subatomic particles known as neutrons.
Which nuclear reaction uses the least expensive materials and produce the least amount of radioactive by-product?
You would probably be talking about nuclear fusion, but it is not available for use and probably won't be for another 50 years, so it's an academic matter. For useful power, fission reactors are the only technology we have, and they all use uranium and produce similar amounts of fission products
A nucleus captures two neutrons and decays to produce one neutron is this process likely to produce a chain reaction?
no because the decay requires 2 neutrons to take place and only gives off 1 neutron
Why does a chain reaction occur when uranium 235 undergoes fission?
Neutrons do this. When 235U undergoes fission, the result is the production of two daughter atoms, each very roughly half the mass of the original atom, a number of neutrons, and heat. The neutrons then can collide with other fissile or fissionable atoms causing them to undergo fission much more quickly than they otherwise would.
What is the minimum mass of a fissionable isotope in which a nuclear chain reaction can occur?
A critical mass is the smallest amount of fissile material needed for a sustained nuclear chain reaction. The critical mass of a fissionable material depends upon its nuclear properties (e.g. the nuclear fission cross-section), its density, its shape, its enrichment, its temperature and its surroundings.The minimum mass for a particular fissionable isotope will always be a sphere, as that is the shape which will lose the least neutrons for a given mass. The behavior of a sphere can be affected by its surroundings, if a neutron reflector is present this will reduce the amount needed. The easiest way to compare materials is to consider a bare sphere with no reflector. In this case Uranium 235 requires a mass of 52 kg and a sphere of diameter 17 cm. Plutonium 239 requires a mass of 10 kg and a sphere 9.9 cm diameter.The Wikipedia article 'Critical Mass' gives a table of other isotopes, but the above two are of most practical interest
How is a chain reactor controlled?
Since the continued chain reaction of a nuclear fission reactor depends upon at least one neutron from each fission being absorbed by another fissionable nucleus, the reaction can be controlled by using control rods of material which absorbs neutrons. Cadmium and boron are strong neutron absorbers and are the most common materials used in control rods. A typical neutron absorption reaction in boron is In the operation of a nuclear reactor, fuel assemblies are put into place and then the control rods are slowly lifted until a chain reaction can just be sustained. As the reaction proceeds, the number of uranium-235 nuclei decreases and fission by- products which absorb neutrons build up. To keep the chain reaction going, the control rods must be withdrawn further. At some point, the chain reaction cannot be maintained and the fuel must be replenished
What is a fission nuclear reaction?
The primary result of a fission reaction is the conversion of mass to energy. In fission, the nucleus split, either through radioactive decay or as result of being bombarded by other subatomic particles known as neutrons.
Which nuclear reaction uses the least expensive materials and produce the least amount of radioactive by-product?
You would probably be talking about nuclear fusion, but it is not available for use and probably won't be for another 50 years, so it's an academic matter. For useful power, fission reactors are the only technology we have, and they all use uranium and produce similar amounts of fission products
A nucleus captures two neutrons and decays to produce one neutron is this process likely to produce a chain reaction?
no because the decay requires 2 neutrons to take place and only gives off 1 neutron
Why does a chain reaction occur when uranium 235 undergoes fission?
Neutrons do this. When 235U undergoes fission, the result is the production of two daughter atoms, each very roughly half the mass of the original atom, a number of neutrons, and heat. The neutrons then can collide with other fissile or fissionable atoms causing them to undergo fission much more quickly than they otherwise would.
What will happen if nuclear fission chain reaction goes on indefinitely?
It can and does in a reactor. Nothing special. However reactors usually require periodic refueling and maintenance, which may require short shutdowns or at least reduced operating power for these activities.
What can happen when a fission chain reaction gets out of control?
A chain reaction has products or byproducts that cause the reaction to continue. One example is a state of nuclear critical mass, in which an atom of u-235 decays to produce fast neutrons (along with other fission fragments), which crash into other u-235 atoms, which release more neutrons. The number of neutrons in the environment increases, and if this is not controlled, then there is a nuclear explosion. That is how an atomic bomb works. Another example is a state of instability in snow on a mountain side. If snow begins to move at the top of the mountain, it pushes the snow below it to give way, this pushes the snow below it to give way in turn, going down the mountainside until the snow runs out or the mountain levels out. This is an avalanche. Another example is a situation where the electric grid is overloaded to the point of instability. A failure in a transformer can cause a power surge that causes another failure, this causes other power surges in other places, resulting in other failures. This produces widespread power outage. Chain reactions continue until some sort of equilibrium is attained, or until the unstable features of the situation have lost their energy. In human terms, the results are often destructive or at least dangerous.
What is produced when billions of uranium nuclei are split apart in a fission reaction?
Fission products; see for details at: http://en.wikipedia.org/wiki/Fission_product.
How does nuclear energy explode?
A nuclear explosion requires two things. First, it requires a critical mass, and second, it requires that the critical mass hold together long enough into the chain reaction that it truly explodes and does not simply come apart. The critical mass comes because certain isotopes spontaneously undergo fission, and, when doing so, produce enough neutrons to cause multiple other atoms to undergo fission also. If there is enough such material in a small enough volume, a chain reaction is produced that consumes most or all of the atoms present. The only natural element to do this is uranium-235. A problem with this is that when the chain reaction starts, there is enough heat to cause the mass to fly apart, destroying the critical mass and ending the reaction. So, building a nuclear bomb requires addressing this problem. It is not an easy problem to overcome, and it probably cannot happen accidentally at all. There has been at least one attempt at building a nuclear bomb that probably failed because of this problem.
What causes fission?
Only certain elements are fissionable, or at least with practical means. The fission of for example the atom U235 happens when it is struck by a slow neutron, it splits, which is fission, releasing two smaller atoms and two or three neutrons (products). The products from the nuclear reaction weigh less then the original atoms. The difference in weight is converted into energy.
Will animals die out where the food chain is broken?
As consumers (chemoheterotrophs), animals cannot produce their own food. Any lost link in the food chain prevents the organisms above that point from surviving, at least in their current position on the chain.
What is a sentence using nuclear fusion?
Fission power is the only realistic source of ecologically sound power, for at least the next 50 to 100 years.
