Describing the Structure of ATOMS

MATTER• Anything that has volume and mass• Everything that exists is matter, and is made of ATOMS

ATOM

• The smallest unit of an element that has all of the properties of that element containing a nucleus within an electron cloud.

MODEL OF THE ATOM

• A conceptual model of the atom showing a small positively-charged nucleus surrounded by orbiting electrons, much like the planets orbit the Sun in our Solar System.

NUCLEUS

• The tiny, dense, positively-charged region in the center of an atom; made up of protons and neutrons

Positively charged protons occupy space

within the nucleus and cause the nucleus to

have an overall positive charge

ELECTRON CLOUD

• All of the area of an atom, outside the nucleus where electrons are found

Negatively charged electrons occupy

the space within the electron cloud and

cause the electron cloud to have an

overall negative charge

SUBATOMIC PARTICLES (the parts that make up the Atom): PROTON, p+

• A positively-charged subatomic particle of the nucleus of an atom that contributes to the mass of the atom

SUBATOMIC PARTICLES: (the parts that make up the Atom):

NEUTRON, n0

• A subatomic particle of the nucleus of an atom that is without charge that contributes to the mass of an atom

SUBATOMIC PARTICLES: (the parts that make up the Atom): ELECTRON, e-

• A negatively-charged subatomic particle of the electron cloud that is involved in the formation of chemical bonds

ELECTRICAL CHARGE

• A form of charge, designated negative, positive, or neutral (has no charge) that is found on the subatomic particles that make up all atoms.

Each electron has a negative charge

Each proton has a positive charge

Neutrons are without charge