Jullian-Atoms and the Periodic Table

A proton is a part of the nucleus. Protons have a positive electric charge.

The brain of the cell, it is the powerhouse that tells the cell what to do.

A neutron is also a part of the nucleus, but, hence the name neutron, it has a neutral charge.

Electrons are particles that move around the outside of a cell, and have a negative charge to balance out the positively charged protons.

An orbital is the region in which electrons are most likely to be found.

A valence electron is in the outermost energy level of an atom, and determines an atoms ability to form bonds.

The periodic law states that when elements are arranged in the periodic table, they will have similarities in their properties.

Horizontal row on the periodic table.

A column in the periodic table.

An ion is a positively charged atom which has just lost an electron.

The atomic number tells you how many protons and electrons are in an atom.

The mass number tells you the number you get when you add the protons and the neutrons together.

Isotopes have a different number of neutrons than that of a regularly found atom.

An atomic mass unit is equal to one twelfth the mass of a carbon-12 atom.

The average atomic mass of an atom is the most commonly found isotopes found in nature or most frequently made.

Most elements on the periodic table are metals. They are shiny solids that can be stretched and shaped.

Nonmetals are found on the right side of the periodic table, they are mostly gases and are typically dull and brittle and are poor conductors.

Semiconductors are nonmetals that under that right conditions can conduct heat and electricity.

Alkali metals are very reactive elements because they all only have one valence electron. They usually form positively charged ions, which are in group 2

All alkaline earth metals, which are in group 2, have two valence electrons, which are less reactive than alkali metals, but can still react to form positive ions.

Transition metals are located in groups 3-12 of the periodic table, which are much less reactive than groups one and two.

Halogens are in group 17 of te periodic table. Halogens are highly reactive, just like alkali metals, they have 7 valence electrons, and will accept the eighth one easily.

Noble gases make up group 18 of the periodic table, and they are highly unreactive, as they have no valence electrons.

A mole is the unit scientists use to measure the amount of particles in an atom.