The Periodic Table and Periodic Law Chapter 6 Section 1 The Periodic Table and Periodic Law

Development of the Periodic Table Antoine Lavoisier (1743 – 1794): compiled a list of all the known elements in the early 1700’s List contained 33 elements Gases Light, heat, dephlogisticated air, phlogisticated gas, inflammable air Metals Antimony, silver, arsenic, bismuth, cobalt, copper, tin, iron, manganese, mercury, molybdena, nickel, gold, platina, lead, tungsten, zinc Nonmetals Sulphur, phosphorous, pure charcoal, radical muriatique, radical fluorique, radical boracique Earths Chalk, magnesia, barote, clay, siliceous earth

Development of the Periodic Table In 1864, English chemist John Newlands proposed an organizational scheme for the elements. He noticed that when the elements were arranged by increasing atomic mass, their properties repeated every eighth element

Development of the Periodic Table In 1869, Lothar Meyer and Dmitri Mendeleev each demonstrated a connection between mass and elemental properties. Mendeleev is given credit for the Periodic Table because he published his first. Mendeleev’s table arranged the elements by increasing atomic mass into columns with similar properties.

Development of the Periodic Table Mendeleev’s table became widely used because he predicted the existence and properties of undiscovered elements

The Development of the Periodic Table Mendeleev’s table was not completely correct though. In some instances, ordering elements by mass created disorder among elements with like properties.

The Development of the Periodic Table Moseley arranged the periodic table in order of increasing atomic number. The statement that there is a periodic repetition of chemical and physical properties of the elements when they are arranged by increasing atomic number is called the periodic law.

The Modern Periodic Table Consists of boxes containing an element name, symbol, atomic number, and atomic mass. The columns of the periodic table are called groups. The rows of the periodic table are called periods.

The Modern Periodic Table Representative Elements Transition Elements

The Modern Periodic Table

Metals Shiny when smooth Solid at room temperature Good conductor of heat and electricity Malleable – can be hammered into sheets Ductile – can be drawn into wires

Metals Group 1: Alkali Metals (except hydrogen) Extremely reactive Often exist as compounds with other elements Li, Na, K, Rb, Cs, Fr

Metals Group 2: Alkaline Earth Metals Groups 3 – 12: Transition Elements Inner Transition Metals Lanthanide series (begins with element 58) Actinide series (begins with element 90)

Non-Metals Occupy the upper right side of the PTE. Generally gases or brittle, dull-looking solids Poor conductors of heat and electricity Only non-metal that is a liquid at room temperature is Bromine

Non-Metals Group 7 (17): Halogens Group 8 (18): Noble Gases

Metalloids Contained in the stair step between the metals and non-metals Also known as semi-metals Have physical and chemical properties of both metals and non-metals