Naming and Classifying the Elements

ELEMENT RIDDLES Curium What doctors do to people, they ____________ 2.The gangsta said to the policeman, “I’ll get you ____________”  Curium Copper

Chemical Symbols of Elements Chemists use symbols to represent elements. For example, O represent oxygen while Fe represents iron.

A standard set of symbols is used to represent elements: The symbol for many of the more common elements uses just the first letter of the name. H= hydrogen O = oxygen C= carbon N = nitrogen F = fluorine B = boron other elements have the first two letters. Li = lithium Al = aluminum He= helium the first letter is always capitalized and the second letter is always lower case

A standard set of symbols is used to represent elements: some of the symbols are not always as you might expect. The letters are taken from their Latin names. Pb= lead Au= gold Ag= silver

English and Latin names for Elements English name Symbol Latin Name Carbon C Carbo Copper Cu Cuprum Iron Fe Ferrum Lead Pb Plumbum Silver Ag Argentum

Periodic Table Origin of the periodic table Chemists in the 10th century wished to organize elements Attempts focused on grouping elements with similar properties

Periodic Table Origin of the periodic table In 1867, Dimitri Mendeleev found patterns in the elements and organized them into table an arrangement of the elements by their physical and chemical properties and masses. The resulting table had holes for elements not yet discovered

Metals, Non-metals, Metalloids Periodic table has interesting patterns Due to Mendeleev’s organization, interesting patterns are created, such as the groups: metals, non-metals and metalloids.

Periodic Table of the Elements

Each horizontal row in the periodic table is a period Vertical columns form groups or chemical families

Periods Horizontal rows of elements are called periods. lists the elements in horizontal rows with masses increasing from left to right. As you go from left to right within a row, the elements gradually change from metallic to non-metallic, then finally to the noble gases at the extreme right.

Groups It also forms vertical columns called groups elements with common properties

Chemical Families Vertical columns of elements are called families and have similar chemical and physical properties. These groups occur as vertical columns on the modern periodic table. There are 5 common families in the periodic table

Alkali Metals (Group 1)

Group 1. Alkali Metals Members: Li, Na, K, Rb, Cs, Fr Properties: Metals: solid, shiny, malleable, silvery, soft, conduct heat and electricity. Super reactive React with water to give H2 gas and an alkaline (basic) solution. Form +1 ions

Group 2. Alkaline Earth Metals Members: Be, Mg, Ca, Sr, Ba, Ra Properties: Metals: solid, shinny, malleable, silvery, soft, conduct heat and electricity Denser than water Very reactive, but not as reactive as the alkali metals Form +2 ions.

Halogens (Group 17)

Group 17. Halogens Members: F, Cl, Br, I, At Properties: Poisonous Pretty colours No-metals Boil at low temperatures (F and Cl are gases at room temperature.) Super reactive Form – 1 ions

Halogens Fluorine Chlorine Bromine Iodine

Noble (Inert) Gases (Group 18)

Group 18. Noble Gases Members: He, Ne, Ar, Kr, Xe, Rn Properties: Very unreactive, nearly inert

Noble Gases

Hydrogen: A Family of One H = Hydrogen Lightest, most common element Melts and boils at low temperatures. Colourless, tasteless, poor heat and electrical conductor, highly flammable.

Hydrogen

Classifying the Elements The elements on the periodic table are divided into 3 main groups based on their properties: Metals Non-metals Metalloids (Semi-Metals)

Classifying the Elements Metals tend to be shiny, malleable, ductile, good conductors and solid at room temperature. (Except mercury, Hg) Non-metals tend to be dull, brittle, poor conductors and are often gases and solid at room temperature. (Except Bromine)

Classifying the Elements Metalloids (Semi-Metals) tend to have some of the properties from each of the above groups. Solid at room temperature, can be shiny or dull, may conduct electricity, not ductile, brittle.

Metals (blue), Non-metals (yellow) metalloids (pink)

Organizing The Elements There are about 100 naturally occurring elements The zigzag staircase line separates the metals on the left from the non-metals on the right.