Final Flashcards
Is energy releases by the fission process?
Yes, the separated fragments are more stable energetically than the original heavy nucleus, energy is released by the process
Define fission
The collision of heavy nuclei (which all have many neutrons and protons) with a neutron that results in the splitting of the nucleus into two similarly sized fragments.
235 U fissioned reaction?
1/0 n + 235/92 U –> 142/56 Ba + 91/36 Kr + 3 1/0 n
Function of the moderator?
To slow down the neutrons that are moving to fast to be efficiently absorbed by other nuclei and cause further fission so they can be useful.
What can the moderator contain?
Regular water, heavy water, or graphite.
What is the function of the coolant?
Used to carry off the heat energy produced by the fission.
What is the coolant material?
Water or carbon dioxide
Why are “spent” fuel rods more radio active than the original fuel?
Because the nucleus fissions and the by product are highly radio active. As a consequence the spent fuel rods are more radio active than the original uranium.
238 U reaction in a fission reactor?
1/0 n + 238/92 U –> 239/92 U –> beta + 239/93 Np –> beta + 239/94 Pu
Why does the mining of uranium pollute the local environment?
Because the contamination of radioactive substances commonly occurs, uranium slowly decays into other substances that are also radio active, uranium ore also contains a variety of radio active elements. So large volumes of waste material that remains after the uranium is chemically extracted from the ore itself is radio active
What is a breed reactor?
Nuclear power reactors that are designed specifically to maximize the production of by product plutonium
Why is it useful to breed fissionable fuel?
So you can dispose of excess plutonium and the fuels can be used in nuclear reactors
Define fusion?
The combination of two very light nuclei to form one combined nucleus
Does fusion result in high amount of energy?
Yes, the combined nucleus is more stable than the original light ones.
Two examples of fusion?
Energy in the stars, and hydrogen bombs
Advantages on solar energy?
Free and abundant
Low environmental impacts
Low operating cost
High public acceptance
Disadvantage on solar energy?
Intermittent
Diffusion
High capital cost
No economic tax or regulatory credit
Pros of wind power?
Sites remote of dense populations can be used Noise level comparable to traffic Can be stored mechanically Very little green house gas emissions Conventional
Cons of wind power?
Far from centres of demand so long transmission lines needed
Tax incentives needed
Require additional infrastructure
Kill wildlife
Noise pollution
Visual pollution
Intermittent so requires back up resources for power.
Cellulostic ethanol?
Cheaper source of energy created by woody plants that contain cellulose, hemicellulose and lignin.
What is an energy source
Material consumed in the generation of power
What is an energy carrier?
responsible for sending, receiving and transporting energy. Must be produced.