Karteikarten
Nuclear Physics
Karten in diesem Stapel (35)
- 1What are the 3 types of ionizing radiation?Alpha, Beta, Gamma
- 2Alpha: structure and ionizing/penetrating propertiesHelium nucleus (two protons, two neutrons)
Heavy, slow, very ionizing, slightly penetrating. - 3Beta: structure and ionizing/penetrating propertiesElectron
Small, fast, moderately ionizing, moderately penetrating - 4Gamma: structure and ionizing/penetrating propertiesElectromagnetic radiation
Massless (a photon), travels at the speed of light, slightly ionizing, highly penetrating. - 5Radioactive decayAn unstable nucleus splits to form new elements, releasing alpha, beta and/or gamma.
Decays are random and cannot be influenced by chemical or physical processes. - 6RadiationThe particles or waves emitted by radioactive substances
- 7Radioactive atomThe nucleus is unstable so it emits particles or waves to form a more stable atom. Process called radioactive decay.
- 8How can radiation be detected?With a Geiger-Muller tube or photographic film (how radioactivity was discovered).
- 9Uses of radiationSmoke detector
Thickness measurement
Sterilising food and medical supplies
Treating cancer - 10Describe the plum pudding modelJJ Thompson's model that an atom is a positively charged sphere with negatively charged electrons scattered about.
- 11How did Rutherford's experiment change the way we think about atoms?Gold foil experiment showed that an atom has a positively charged nucleus and the nucleus contains most of the matter of the atom. Also has negatively charged electrons.
- 12What can alpha rays penetrate?The air
- 13What can beta radiation penetrate?Air and paper
- 14What can gamma radiation penetrate?Everything but thick lead or concrete
- 15Define isotopeA different version of an element that has a different number of neutrons
- 16If hydrogen-1 has 1 proton, 0 neutrons, 1 electron, how many P.N.E does hydrogen-2 and hydrogen-3 have?They all have the same amount of protons and electrons, but hydrogen-2 has 1 neutron and hydrogen-3 has 2 neutrons.
- 17Platinum (78) decays by beta emission. What element does it become?Gold/Au (79)
- 18What makes up the nucleus?:LTErkjmgProtons (positive) and neutrons (neutral)
- 19How are electrons chargedertgl5tk?No
- 20How do you calculate neutrons?You subtract the atomic number from the isotopic mass
- 21Define half lifeTime taken for a quantity to fall to half its original value
- 22What equation is used to work out how much energy is released?E = mc2
E = Energy
m = mass
c = speed of light in a vacuum - 23Define fissionWhen the nuclei of atoms break apart
- 24Define fusionWhen the nuclei of atoms join together
- 25Which elements are used in nuclear fission and why?Plutonium and uranium, because their nuclei are very large and easy to split apart.
- 26How do you create energy with uranium or plutonium?You fire neutrons at their nuclei which breaks them in two and releases energy.
- 27What is a chain reaction?During fission, each split of an atom sets off more reactions, which can continue unaided.
- 28Describe what happens to the protons and neutrons when nuclear fusion occurs between two nuclei.The nuclei of a Hydrogen-2 atom and a Hydrogen-3 atom join to make a large nucleus (Helium). Energy is released when this happens.
- 29The nuclei of hydrogen have a positive charge. How does this affect the chances of nuclear fusion occurring?Reduces the chance of fusion, as nuclei do not get near enough to each other.
- 30What conditions are needed to make hydrogen nuclei fuse together?Extremely hot temperature and confinement to overcome repulsion.
- 31Where in the solar system is the temperature high enough to start fusion?The sun and other stars.
- 32What is the force that usually stops two nuclei getting close together?Electrostatic repulsion
- 33What is the force that holds the protons and neutrons together in the nucleus?Strong nuclear force
- 34Why is the inside of the sun a suitable environment for nuclear fusion?Because it's hot enough to blow apart the nuclei from the electrons and gravity confines the nuclei so they can fuse.
- 35Which elements are usually involved in nuclear fusion?Hydrogen-2 and hydrogen-3