Download Atomic Structure [PowerPoint]

Atomic Structure
Atom
• The smallest part of an element with all
the properties of the element.
• Also called the building blocks of matter
• Composed of protons, neutrons, &
electrons.
• *
Subatomic Particles
Type
Charge
Mass
Location
proton
positive
1
nucleus
neutron
neutral
1
nucleus
electron
negative
0
electron
cloud
Protons
• The protons determine the element.
• The number of protons is equal to the
atomic number.
• Any atom with the same number of
protons is the same element.
• *
Mass Number
• The mass number is equal to the total
number of protons plus the number of
neutrons in the nucleus of an atom.
• Atoms of the same element may have
different number of neutrons, thus varying
mass numbers.
• *
Isotopes
• Atoms of the same element with different
number of neutrons.
• Atoms of the same element with different
mass numbers.
• *
Nucleus
• What holds the protons together within the
nucleus?
• A force called the strong nuclear force
overcomes the electromagnetic force that
repels the positively charged protons.
• *
Electrons
• The number of electrons in a neutral atom
is equal to the number of protons.
• Electrons are located in the electron cloud.
• *
Electron Cloud
• Electrons are separated within the electron
cloud because of their like charge repels
them.
• They are divided into energy levels and
further divided into orbitals.
• Orbitals can overlap.