Qrtr 4 final

Learning Goal for this section:
Explain and compare nuclear reactions, (radioactive decay, fission, and fusion)
the energy changes associated with them and their associated safety issues.
Notes Section:
The nucleus of an atom consists of the protons and neutrons, which each have
a mass of 1 amu. Electrons have mas, but it is barely recognizable.
Isotopes are atoms with a divergent number of neutrons. Some of these
isotopes are radioactive, but not all of them are.
When any living thing comes into existence, it is "born" with a certain number
of carbon atoms. Everything living thing is created with the same amount of
Carbon. Over time, it will decay and you can tell how old the object is by how
many carbon atoms are left. You need to know the half life of the element to
do this, since you calculate how old the organism is by how many half-lifes the
carbon has undergone.
Alpha Particles
238 is mass, 92 is protons
In the case of Uranium, it looks like 238
92 U
238
92 U ---> 90
234
Th
---->
4
Beta Particles
Negative- 8p , 6n 14
6
2 He
C --->
Positive- p-5 8
B ---> 8 4 Be +e +
n-3
5
. To find the alpha particle decay, you just subtract a
helium from it. Since heliums mass is 4, and the protons
are 2, 238--> 234 and 92--> 90. Then you stick a helium
on the end.
14
7 N 7p, 7n
so they become protons. It doesn't affect the mass,
but it changes the element. (In this case, from Carbon
to Nitrogen).
Beta particles take the negative charge from neutrons,
Gamma Radiation - Just energy being released, associated with alpha and beta radiation.
When it interacts with a & b, they get really excited and give off even
more energy.
4
Half Life- The time it takes for a radioactive isotope to lose half it's mass (it's
really not "lost", it's just converted to a different substance).