Atomic Theory

Atom:

• Smallest particle of element

• Has properties of element

Subatomic Particles:

• Smaller than atom

Nucleus:

• Tiny region at centre of atom

• Has protons and neutrons (p+ & n⁰)

• Number of protons determines charge of nucleus & identity of atom

Electron Shell:

• Region that electrons occupy

• Account for 99.9% of atom volume

• Electrons spread out like cloud of negative charge existing in whole region at once

Protons:

• Positive charge(p+)

• Charge 1+

• 1 amu (Atomic mass units)

• Location Nucleus

Neutrons:

• Neutral Charge (n0)

• Charge 0

• 1 amu (Atomic mass unit)

• Location Nucleus

Electrons:

• Negative charge (e-)

• Charge -1

• Mass Negligible (Doesn’t matter)

• Location surrounding nucleus