Fundamental Atom Forces
• ____________ of the 4 forces
• Exerted by _________ objects in the universe
• It is the force of _____________ between objects
• Second strongest of the 4 forces
• The force that keeps atoms ______________.
• Deals with attraction and repulsion so it also deals with
positive and negative charges.
3. Strong Nuclear Force-
• Strongest of the 4 forces
• The force that holds quarks together inside protons and
neutrons and keeps the protons and neutrons
____________ the nucleus.
4. Weak Nuclear Force-
• The force responsible for ____________ decay.
• Least familiar of the 4 forces
• Discovered x-rays which lead other
scientists to discover radioactive particles or
• Born Dec. 15, 1852
NoblePrize in 1903
• Died Aug. 25, 1908
History behind Nuclear Radiation:
1. The “Father of Nuclear Radiation”
was Henri Becquerel (1800’s).
A) Was the 1st to research
B) Discovered the first
radioactive element, __________.
2. Other leaders in the field of
nuclear radiation research included
Pierre and Marie Curie.
A) Discovered 2 other
____________ and ___________.
What makes an atom radioactive?
• A _________ nuclear
force! This creates an
1. Radioactivity- ________ that is emitted
from radioactive elements in the form of
_________ or a _______.
2. Types of Radiation (3 kinds)-
A) Alpha Particles- 1 _______ particle
released from an element gives off 2
protons and 2 neutrons.
* have an overall ______ charge
* _________ form of radiation
B) Beta Particles- 1 _______ particle is
made by the breakdown of neutrons in
the _________ to make an electron inside
* more penetrating than alpha
C) Gamma Rays- They are a form
of electromagnetic energy or wave.
* have hi frequencies and have the
1. Radioactive Decay- when unstable
nuclei of atoms OR isotopes of atoms
undergo nuclear reactions to become
________. THIS FORMS A ______
ELEMENT! (called transmutation)
A) Parent Material- starting element
B) Daughter Material- ending element
2. Types of Decay-
A) Alpha Decay-
* nucleus releases an _________
________ (2 P and 2 N)
* reduces atomic # by _____
* reduces mass # by ______
B) Beta Decay-
* releases a ________ ________ (1e-
released from the nucleus)
* increases atomic number by_______
* mass # does ________ change
C) Gamma Decay-
* emits a gamma ray
* _________ does NOT change
Decay Series- the step by step process by
which a radioactive element ________.
Half Life- the time it takes for _____
of the atoms in an _______ to
Nuclear Fission and Fusion:
1. Nuclear Fission- occurs when an
atom’s nucleus is ________ into 2
_______ nuclei with about the
A) To occur, an atom’s nucleus
is hit with with a neutron
B) The products are 2 new
nuclei and 2-3 neutrons
C) 1 split does not give off a
large amount of energy. BUT, a
chain reaction occurs (a series
of fission reactions). This
___________ a lot of energy.
Ex.) atomic bomb
2. Nuclear Fusion- Occurs when 2 nuclei
with small masses _______to form a
nucleus with a large mass.
A) It’s a thermonuclear
B) Hard to reach temperatures
for fusion on Earth, but happens
naturally on the ________.
C) Advantages of Fusion over
* Releases ______ energy
* produces ______ radioactive
* Fuels (water components) needed
to start a fusion reaction are in
D) Disadvantages of Fusion-
* Hard to start, control, and
sustain these reactions.
* Hard to reach the needed
There are several ways to detect radioactivity.
Two of the most common are the
electroscope and the Geiger counter.