Project 1

Group 6
In 1812 Eugene Goldstein noticed during an experiment there were
hydrogen nuclei. Those were also known as protons, or even the
hydrogen in when separated from it’s electron.
The proton has a positive charge.
What are their properties?
A proton is a subatomic particle with an electric charge of one positive
fundamental unit
Protons are much larger and heavier than electrons
It is about 1836 times the mass of an electron
Protons are found in the nucleus of atoms
quark structure of the proton
The number of protons in the nucleus determines the
chemical properties of the atom
Protons are observed to be stable and their theoretical
minimum half-life is 1×1036 year
The Neutron is the neutral part of the atom
Discovered by Walther Bothe, Irène Joliot-Curie, Frédéric Joliot, and James
Chadwick in the early 1930’s
The neutron has to do with the strong force which holds the atom together
(gravity is too weak at this level to hold the nucleus together), but when
an atom is too large the atoms fall apart (this releases radiation).
What are their properties?
Neutrons are subatomic particles with no net
electric charge
They are also found in the nucleus of an atom
Quark structure of the neutron
The number of neutrons determines the
isotope of an element
Neutrons consist of two down quarks and
one up quark
An electron is the negatively charged part of the atom
Discovered by J. J. Thomson in 1897
Discovered with the use of cathode ray tube
Used in many applications such as: radiation therapy, welding, electron
microscopes, etc….
What are their properties?
An electron is a fundamental subatomic particle that carries a negative
electric charge
Electrons are found outside the nucleus of an atom
Together with the atomic nuclei (protons and neutrons), electrons make
up atoms
An electron’s mass is approximately 1 / 1836 of the proton
Electron mean lifetime is >4.6x10^26 years
Electrons can also act as waves
Nuclear and Hyphen notation
Hyphen Notation
• Hyphen notation is the written name of the
element plus its mass number.
• Hydrogen-1
• Helium-3
• Uranium - 235
Nuclear Notation
• Uses the first letter of the element plus it’s
mass number and atomic number
Mass number
atomic number 1
Why does it matter?
• Nuclear and hyphen notation allow us to express
different forms of the same isotope
• For example, there are more than one hydrogen
so simply writing “hydrogen “ does not mean one
specific isotope
• So by using hyphen notation, we are able to
express a single isotope of hydrogen by showing
it’s mass number or using nuclear notation to
show hydrogen’s mass number AND atomic
For more information
Elemental Identities!
Q: What gives an element its
A: The atomic number (number of
protons in the nucleus) provides a
unique identity for elements because
each element contains a different
number of protons.
Example: Atomic # is 6…..
It must be Carbon!!!!