Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
gcse science P4 - H
specific for ocr gateway additonal science B.
| Question | Answer |
|---|---|
| how are artificial radioisotopes produced? | by bombarding atoms with the neutrons present in a nuclear reactor |
| why are neutrons easily captured by many nuclei? | they're uncharged |
| what are the two isotopes of natural uranium? | uranium-235 and uranium-238 |
| what is used as a fuel in power stations? | enriched uranium |
| what does the enriched uranium contain more of? | uranium-235 isoptope than occurs naturally |
| when does fission occur? | when a large unstable nucleus is split up and energy is released |
| what is this energy released as? | heat |
| how is this energy used in nuclear power stations? | -heat used to boil water -this produces steam -the pressure of the steam turns the turbine -the turbine turns the generator, producing electricity |
| how is energy made in a nuclear power station? | by bombarding atoms of uranium-235 with neutrons, which causes the nucleus to split and release energy |
| what can a typical fission be shown as? | 235 1 90 143 (1 ) U + n - Kr + Ba + 3( n)+ γ-rays 92 0 36 56 (0 ) |
| what is a chain reaction? | when extra neutrons emitted cause further uranium nuclei to split. |
| what does a chain reaction produce? | large amounts of energy |
| what does nuclear fission produce? | radioactive waste |
| what has to be done with radioactive waste? | disposed safely and handled carefully |
| what is an example of very low-level waste? | that produced by medical applications |
| how is low-level waste disposed of? | placed in sealed plastic bags then buried or burned under strict controls |
| how is other low-level waste disposed of? | embedded in glass discs and buried in the sea |
| what is an example of high-level waste? | spent fuel rods |
| how is high-level waste disposed of? | re-processed to make more radioactive materials |
| how is the output of a nuclear reactor controlled? 1 | -graphite moderator between the fuel rods slows down the fast-moving neutrons emitted during fission. slow-moving neutrons are more likely to be captured by other uranium nuclei |
| how is the output of a nuclear reactor controlled? 2 | boron control rods can be raised or lowered. boron absorbs neutrons, so fewer neutrons are available to split more uranium nuclei. |
Created by:
jirwin
Popular Physics sets