View
- Term
- Definition
- Both Sides
Study
- All (53)
Shortcut Show
Next
Prev
Flip
PHYS 102: Final
1) An atom with an imbalance of electrons to protons is
|
ion
|
2) Generally speaking, the larger a nucleus is, the greater its
|
instability
|
3) Which is the smallest particle listed below?
A) an atom B) a quark C) a neutron D) a proton E) a molecule
|
quark,
|
4) Uranium—235, uranium—238, and uranium—239 are different
|
isotopes
|
5) The weight of matter comes mostly from its
|
protons
|
6) Carbon dating requires that the object being tested contains
|
organic material
|
7) The end result of radioactive decay can be a different
|
isotope, atom OR element
|
8) Radioactivity in the world is something
|
as old as the world itself
|
9) Which of the following isotopes is radioactive?
A) carbon—14 B) carbon—12
C) Both are radioactive. D) Neither are radioactive in nature.
|
carbon-14, Stability of a nucleus is dictated by the neutron/proton ratio. Too large or too small and the nucleus is unstable. The greater neutron/proton ratio in carbon-14 is too large, making the nucleus sufficiently unstable that it emits a beta particle, converting to nitrogen-14.
|
10) Electric forces within an atomic nucleus tend to
A) hold it together.
B) push it apart.
C) neither of these.
|
push it apart
|
11) If two protons are added to an oxygen nucleus, the result is
A) heavy oxygen.
B) neon.
C) fluorine.
D) nitrogen.
E) sodium.
|
fluorine
|
12) The atomic mass number of an element is the same as the number of its
|
neucleons
|
13) The function of graphite in the first atomic reactor was to
|
slow fast neutrons
|
14) Which has the greatest number of protons in its nucleus?
A) lead B) silver C) mercury D) gold
|
lead
|
15) Which radiation has no electric charge associated with it?
A) gamma rays B) beta rays C) alpha rays D) all of these E) none of these
|
gamma rays
|
16) The atomic number of an element is the same as the number of its
|
protons
|
17) Carbon—14 is produced in the atmosphere principally by
|
cosmic ray bombardment
|
18) To change mercury into gold, a pair of protons must be
A) added to the mercury nucleus. B) removed from the mercury nucleus.
C) both of these. D) neither of these.
|
none of these
|
19) Which experiences the least electrical force in an electric field?
|
gamma ray (most is alpha particle)
|
20) Most of the radioactivity we personally encounter comes from
|
the natural environment
|
21) Compared to the mass of a uranium nucleus before splitting, the pieces it splits into have
A) the same mass. B) less mass. C) more mass.
|
less mass
|
22) When radium (A = 88) emits an alpha particle, the resulting nucleus has atomic number
|
86
|
23) When an alpha particle is ejected from a nucleus, the nucleus then has less
|
charge
|
24) The mass of an atomic nucleon is nearly
|
2,000 x mass of electron
|
25) Control is exercised in a nuclear reactor by
|
Absorbing excess neutrons with control rods
|
26) U-235 and Pu-239 are both
|
all of these (radioactive isotopes, heavier than lead, fissionable isotopes)
|
27) In an electrically neutral atom, the number of protons in the nucleus is balanced by an equal number of
|
orbital electrons
|
28) The half—life of carbon 14 is 5730 years. If a 1—g sample of old carbon is 1/8 as radioactive as 1 g of a current sample, then the age of the old sample is about
|
17190 years (HOW!!!)
|
29) When U—235 undergoes fission, the two nuclei that result have a total of
|
92 protons
|
30) In the fissioning of uranium, a chain reaction is caused by
|
ejected neutrons
|
31) The source of the Earths natural heat is
|
radioactive decay in the Earth's core.
|
32) It's impossible for a hydrogen atom to emit an alpha particle.
|
TRUE
|
33) A gram of radioactive material has a half—life of one year. After 4 years, how much radioactive material will be left?
|
1/16th - none of these
|
34) Electrical forces inside a nucleus contribute nuclear
|
instability
|
35) The half-life of an isotope is one day. At the end of two days the amount that remains is
|
one-quarter
|
36) In nuclear fission and nuclear fusion reactions, the amount of mass converted to energy is about
|
...
|
37) The volume of matter comes mostly from its
|
electrons
|
38) Different isotopes of an element have different numbers of
|
neutrons
|
39) There is a greater proportion of carbon—14 in
|
new bones
|
40) The reason a granite block is mostly empty space is because the atoms in the granite are
|
mostly empty space themselves
|
41) The half-life on an isotope is one day. At the end of three days, how much of the isotope remains?
|
one eight
|
Characteristics of alpha radiation
|
4 He
2
Alpha's composition the nuclei
Alpha's mass 4
Alpha's charge 2+
|
Characteristics of beta radiation
|
Beta's composition electrons
Beta's symbol 0
-1
Beta's mass 0
Beta's charge 1-
|
Characteristics of gamma radiation
|
Gamma's composition energy
Gamma's symbol 0 r
0
Gamma's mass 0
Gamma's charge 0
|
Discuss two useful applications of radioactive isotopes.
|
...
|
Distinguish between an isotope and an ion.
|
...
|
What is meant by radioactive half-life? Give an example.
|
...
|
Discuss the hazards and benefits of nuclear power.
|
...
|
In a reactor core—what is a control rod? What is a moderator?
|
-moderator slows down the speed
of the neutrons
-control rods prevent the chain reaction happening too quickly by absorbing nuetrons
|
What is a chain reaction? Give an example.
|
-a series of reactions that are triggered by an initial reaction.
-A nuclear reaction, in general, occurs when two isotopic nuclei collide, producing molecules different from the reactants, usually different species.
-fission and fussion
|
What is critical mass?
|
the amount of fissile material needed to sustain nuclear fission
|
What is supercritical mass?
|
an increasing rate of fission
|
E=mc2-----Discuss the application of this equation to nuclear power.
|
...
|