The Atom

The AtomAn Atom Is So SmallA penny contains 2 x 1022 atoms Or20,000,000,000,000,000,000,000 atoms!

It would take a stack of 50,000 aluminum atoms to equal the thickness of a sheet of aluminum foil!

Even though an atom is tiny, it consists of even smaller particles: ProtonsNeutronselectronsWhats Inside an Atom

BrainPOPAtomProtons are positively charged particles of the nucleus

All are identical

Each proton has an amu (atomic mass unit) of 1Inside the Atom: Protons

Neutrons are the particles of the nucleus that have no charge

All neutrons are identical

While neutrons are a bit larger than protons, they are not enough bigger to have a larger amu. Theirs is also =1.Inside the Atom: Neutrons

Electrons are the negatively charged particles in atoms

Likely to be found around the nucleus within electron clouds

Charges of protons and electrons are opposite but equal in sizeOutside the Atom: Electrons

Charge of An Atom

An atom is neutral (has no overall charge) because there are an equal number of protons and electrons

If there is an inequality between protons and electrons, the atom becomes a charged particle called an ion.BrainPOPIonsIf protons > electrons = positive charge

If electrons > protons = negative charge

Electrons are tiny in mass compared with protons and neutrons

Mass 1 proton 1800 electrons! So small its mass is usually considered to be zero!Charge of An Atom

How Do Atoms of Different Elements Differ?Lets build the simplest atomthe hydrogen (H) atomProtonElectron

Can we build bigger atoms?Sure! Try this on your own paper

A carbon atom has 6 protons, 6 neutrons, and 6 electrons or

An oxygen atom that has 8 protons, 9 neutrons, and 8 electrons

Next, lets build a Helium atomProtonsNeutronsElectron

Are All Atoms of an Element the Same?Not necessarily. Some atoms have an unequal number of protons and neutrons. We call these atoms isotopes.

In an isotope, the number of protons in an element always remains the same. The neutrons change.

Do protons and neutrons have to be equal? Nope! However

The Number of Protons Determines the Element

The number of protons in the nucleus of an atom is the atomic number of that atom.

How Can I Tell Which Element is Which?

Lets reviewWhat is the charge, location, and mass of a proton?

A proton has a 1+ charge, is found in the nucleus, and has a mass of 1 amu

Lets reviewWhat is the charge, location, and mass of a neutron?

A neutron has no charge, is found in the nucleus, and has a mass of 1 amu

Lets reviewWhat is the charge, location, and mass of an electron?

An electron has a 1- charge, is found in the electron cloud, and has almost no mass.

Summarize 3 2 1 Review!On a sticky note write your name and:3 parts of an atom2 largest particles in the atom1 particle with a negative charge

Place it on the boardgently.