Physics: Chapter 34
In which of these processes is an element of matter changed into a completely different element?
C. both of these
Present-day research in nuclear fusion uses
C. both of these
Three isotopes that undergo nuclear fission are
D. U-233, U-235, U-239
When uranium-238 absorbs a neutron, it
becomes a beta emitter
In the fissioning of uranium, a chain reaction is caused by
ejected neutrons
Compared to the mass of a uranium nucleus before splitting, the pieces it splits into have
less mass
In a nuclear fission and nuclear fusion reactions, the amount of mass converted to energy of other forms is
less than 1%
The most abundant element in the universe is
A. hydrogen
When two light atoms fuse together, mass
A. is converted to kinetic energy of neutrons
Energy released by the suns results from the process where in atomic nuclei
B. combine
A nuclear process that has relatively few radioactive by-products is
B. fusion
In both fission and fusion, mass
B. is converted to kinetic energy
Electrical forces inside a nucleus contribute nuclear
Instability
the effect of putting small amounts of PU-239 with U-238 is converting U-238 to
Pu-239
Control is exercised in a nuclear reactor by
absorbing excess neutrons with control rods
A chain reaction grows when the average number of liberated neutrons that go on to cause further fission is
greater than one
when a lumo of uranium is broken into smaller pieces, the total surface area of the lump
increases
Uranium-235, uranium-238 and uranium-239 are different
isotopes
When neptunium emits a beta particle the result is
plutonium
In a breeder reactor
uranium is converted into plutonium