ATOMSIt’s what makes us up!

ATOMS

•The smallest particle which an element can be divided and still be the same substance.

Atom Size

•1 Penny= 2 x 10^22 Cu and Zn ATOMS

•That’s (20,000,000,000,000,000,000,000)

•Thickness of aluminum foil is about 50,000 aluminum atoms stacked up!

Parts of the ATOM

•Protons (+)

•Neutrons (0)

•Electrons (-)

NUCLEUS

Nucleus

•ALL Protons (+) are identical.

•Mass= 1 amu (atomic mass unit)

•ALL Neutrons (0) are identical.

•Mass= 1 amu

NUCLEUS

•Most of the mass of an atom is found in the nucleus.

•1 amu= 1.7 x 10^ -24 g

PROTONS

•Found in the nucleus

•Positive charge

•Mass= 1 amu

•AMU= atomic mass unit- SI unit for measuring mass of atomic particles)

Atomic Number

•Atomic Number= # of protons in an atom

•ALL atoms of an element have the same number of protons!

Neutrons

•Found in the nucleus

•Neutral= no charge

•Mass= 1 amu (atomic mass unit)

MASS NUMBER

•Mass Number= protons + neutrons

ELECTRONS (-)

•Found in Electrons Cloud Outside the nucleus.

•In an atom:

•# of protons = # of electrons

•The atom has no charge!

•Mass of an electron= almost 0 (We will call it zero)

ELECTRONS (-)

•Comparing the masses

•1,800 electrons = 1 proton

Model of Atom

IONS

•Charge particles

•Positive ion

•Protons (+) > Electrons (-)

•Negative ions

•Electrons(-) > Protons (+)

ISOTOPES

•Atoms that have a different # of neutrons than protons.

•The number of protons do not change!

ISOTOPES

Name that Isotope!

•Write the name of the element!

•Follow that with a hyphen.

•And the mass of the isotope!