Review Chapter 10
General, Organic, & Biological Chemistry
Janice Gorzynski Smith
Chapter 10 Concepts
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


Interpret Atomic number and mass number
Know radioactive particles: alpha, beta, positron, gamma
Write & solve radioactive decay equations
Determine the number of half lives that pass in a given
amount of time.
 Familiar with measurements of the amount of radioactivity
 Familiar with measurements of radiation absorbed
 Understand how radioisotopes are used in medicine
2
Atomic Symbols & Nuclear Particles
atomic number (Z) =
alpha particle: a
the number of protons
or
mass number (A) =
the number of protons
+
the number of neutrons
beta particle:
β or
mass number (A)
positron: β+
or
atomic number (Z)
12
6
number of protons 6
number of neutrons 12 – 6 = 6
gamma ray:
0
e
−1
0
e
+1
C
g
4
He
2
Nuclear Equations & Half Life
original
nucleus
radiation
emitted
new
nucleus
=
4
He
2
0
e
−1
+
0
e
+1
radiation
emitted
g
The half-life (t1/2) of a radioactive isotope is the time it
takes for one-half of the sample to decay.
Radioactivity
amount of radioactivity
1 Ci = 3.7 x 1010 Bq.
radiation absorbed
The rad—radiation
absorbed dose
The rem—radiation
equivalent for man
Radioisotopes can be
injected or ingested to
determine if an organ is
functioning properly or to
detect the presence of a
tumor.