SNC 1D1 - Ch 6 Review (Atomic Theory, Structure of the Atom & The Periodic Table)

Atomic Mass

# protons + # neutrons in an element. This determines the MASS of the nucleus.

Atomic Number

# protons in an atom. This determines the IDENTITY of an element.

Periodic Table

A grid of the elements organized into PERIODS and GROUPS to show patterns in the way the elements look and act (structure & behaviour)

neutron

A subatomic particle that has NO CHARGE and that is found in the nucleus of an atom and has a mass of 1u

electron

A subatomic particle that has a NEGATIVE charge... almost no mass

proton

A subatomic particle that has a POSITIVE charge and that is found in the nucleus of an atom and has a mass of 1u

Atomic Mass Unit

A unit of mass that describes the mass of a proton or neutron (symbol is u)

Isotopes

Atoms with the SAME # PROTONS (same atomic number) but DIFFERENT # NEUTRONS (different atomic mass)

Group

COLUMN of the periodic table read from top to bottom. Elements in the same column have the same number of valence electrons.

Metals

Elements found on the LEFT SIDE OF THE PERIODIC TABLE. They are lustrous, malleable, ductile, conduct heat and electricity, and are almost all solid at room temperature.

Nonmetals

Elements found on the RIGHT SIDE OF THE PERIODIC TABLE. They are gasses or a dull, powdery solids and not good conductors of heat and electricity

Metalloids

Elements found on the STAIRCASE LINE. They have properties of both metals and non-metals.

Alkali Metals

Family of elements located in Group 1

Halogens

Family of elements located in Group 17

Noble Gases

Family of elements located in Group 18

Alkaline Earth Metals

Family of elements located in Group 2

Aristotle

He claimed that all matter is made from earth, water, air and fire.

Period

ROWS of the periodic table read from left to right. One proton and one electron are added from one element to the next.

nucleus

The positively charged CENTRE OF THE ATOM, which is made up of protons and neutrons.

Bohr

The scientist that demonstrated that electrons move around the nucleus in fixed orbits

Thomson

The scientist that discovered the ELECTRON. He developed the plum pudding model of the atom.

Chadwick

The scientist that discovered the NEUTRON. He also said that a neutral atom has the same number of protons and neutrons.

Rutherford

The scientist that discovered the PROTON, and developed the theory that atoms are mostly empty space. He conducted the GOLD FOIL experiment

Dalton

The scientist that hypothesized that different elements are different, matter is conserved during a chemical reaction

Democritus

This scientist developed the theory of the "indivisible" atom