What is the difference between the isotopes Uranium-238 and Uranium-235?
Uranium-238 has three more protons.
Uranium-238 has three more neutrons.
Uranium-238 has three more electrons.
There is no difference.
An alpha particle is the same as a(n) ___.
helium nucleus
beta particle
hydrogen nucleus
electron
Nuclear fusion produces energy when ___.
two atomic nuclei combine
an atomic nucleus splits
a chemical reaction occurs
helium transmutes into hydrogen
Nuclear fission converts ___.
small atoms into larger atoms
small amounts of mass into energy
small amounts of energy into mass
small atoms into molecules
An unstable nucleus ____.
increases its nuclear mass by fission
expels all of its protons
increases its half-life
emits energy when it decays
The identity of an element, the atomic number, is determined by its number of _.
Electrons
Neutrons
Protons
Which radiation has the poorest penetration (lowest ionization energy) but can cause the most damage to a cell?
Alpha particles
Beta particles
Gamma rays
They all have the same strength
What particle is needed to complete this nuclear reaction? 222 Rn → 218 Po + ____ 86 84
4 α 2
0 ẞ -1
0 γ 0
1 n 0
When a uranium-235 nucleus is struck with a neutron, xenon-144 and strontium-90 nuclei are produced, along with some neutrons. How many neutrons are produced?
0
1
2
3
The iodine-131 nuclide has a half-life of 8.0 days. If you originally have a sample containing 728-g of I-131, after 48 days you will have ___.
11.4 g
22.75 g
6.3 g
45.5 g