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The Periodic Table. Father of the Periodic Table. In the early 1800s several scientists tried to organize the elements In 1869 Dmitri Mendeleev was able to arrange elements by their chemical properties , using rows and columns
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Father of the Periodic Table • In the early 1800s several scientists tried to organize the elements • In 1869 Dmitri Mendeleev was able to arrange elements by their chemical properties, using rows and columns • We call this table periodic because it shows a periodic, repeating pattern of properties of the elements.
13 Al Aluminum 26.981 Reading the Periodic Table Atomic number Chemical symbol Element name Atomic mass
Pop Quiz Question #1 Who is Dmitri Mendeleev? • He discovered the most elements. • He created the periodic table • He named the periodic table • He discovered Mendelevium (atomic number 101)
Groups and Periods • Elements in a vertical column have similar physical and chemical properties • Vertical columns are called groups or families • The chemical properties of elements in horizontal rows show a progression • Horizontal rows are called periods
Pop Quiz Question #2 Which way is a group organized? A group is a row. A group is a column.
Trends on the Periodic Table • Sizes of the atoms decrease as we move from left to right across a period • This is due to the increasing number of protons in the nucleus, so the electrical attraction between the nucleus and orbiting electrons gets stronger and pulls the electrons closer to the nucleus
Atom size decreases Atom size increases
Pop Quiz Question #5 How does the size of atoms change as you go from left to right across the periodic table? Atoms get larger moving left to right Atoms get larger moving right to left Atoms get larger moving down a group Atoms get larger moving up a group
Three Main Regions Metalloids –stair steps Nonmetals – on the right Metals –on the left
Characteristics of Most Metals • Shiny • Malleable and ductile (can be shaped into sheets and wires) • Good conductors of heat and electricity • Solidat room temperature (except Mercury)
How many things can you think of that have Transition Metals in them?
Metalloids lie on either side of these “stair steps” They share properties with both metals and non-metals Si (Silicon) and Ge (Germanium) are very important “semi-conductors”
Nonmetals Brittle Do not conduct electricity
Families on the Periodic Table • Elements on the periodic table can be grouped into families based on their chemical properties. • Each family has a specific name to differentiate it from the other families in the periodic table. • Elements in each family react differently with other elements.
Hydrogen • Hydrogen belongs to a family of its own. • Hydrogen is a highly reactive gas. • Hydrogen was involved in the explosion of the Hindenburg. • Hydrogen is promising as an alternative fuel source for automobiles
Alkali Metals Soft, silvery colored metals Very reactive!!!
ALKALI METALS Group 1 • Hydrogen is not a member, it is a non-metal • All are metals and solid at room temp • 1 Valence Electron • Soft and silvery, shiny • Very reactive, esp. with water • Conduct electricity Image: http://www.learner.org/interactives/periodic/groups2.html
What would you expect from Francium?!?! Alkali Metals reacting with water: • Li (Lithium) • Na (Sodium) • K (Potassium) • Rb (Rubidium) • Cs (Cesium)
Alkaline Earth Metals Silvery-White Metals (shiny) Fairly reactive Many are found in rocks in the earth’s crust
ALKALINE EARTH METALS Group 2 • Metals • Solids at room temp • 2 electrons in the outer shell • White, silvery, and malleable • Reactive, but less than Alkali metals • Conduct electricity
Transition Metals & Conductors of heat/ electricity Malleable
TRANSITION METALS • Almost all are solids at room temp (Hg) • Malleable • Good conductors of heat and electricity. • 1 or 2 Valence Electrons • Less Reactive than Alkali and Alkaline Earth • Can bond with many elements in a variety of shapes.
Pop Quiz Question #6 What are the three main parts to the periodic table? Solids, liquids, gases Protons, neutrons, electrons Metals, nonmetals, metalloids
BORON FAMILY Group 13 3 electrons in the outer shell Most are metals Boron is a metalloid Reactive Solid at room temp
CARBON FAMILY Group 14 4 electrons in the outer shell Contains 3 metals, 2 metalloids, and 1 non-metal Carbon (C) Reactivity varies Solids at room temp
NITROGEN FAMILY Group 15 5 electrons in the outer shell Can share electrons to form compounds Contains 1 metals, 2 metalloids, and 2 non-metals Reactivity Varies Nitrogen is the only gas at room temp, rest are solids
OXYGEN FAMILY Group 16 6 electrons in the outer shell Contains 2 metals, 1 metalloid, and 3 non-metals Reactive Oxygen is a gas, the rest are solids at room temp
Halogens Most are Poisonous Reactive
Halogens Group 17 7 electrons in the outer shell Non-metals, Uus is unknown Very reactive - are often bonded with Group 1 Alkali Metals Volatile Has 2 gases, 1 liquid (Br), and 2 solids
Halogen Uses Chlorine Gas was used as a chemical weapon during World War I. It was used by the Nazis in World War II.
Noble Gases Unreactive Gases at room temperature
Noble Gases Group 18 Gases at room temperature Non-metals Full outer shell (8 e-) Helium (He) has only 2 electrons in the outer shell = Full Not reactive with other elements Also called inert gases
Neon Signs with Noble Gases Neon Argon Helium Krypton Xenon
Lanthanide Series Actinide Series Rare Earth metals Radioactive metals
Lanthanides and Actinides Lanthanides Actinides Some are Radioactive The rare earths are silver, silvery-white, or gray metals. Conduct electricity
The Elements Song • Sung by Tom Lehrer, from the 1959 periodic table
The Elements Song • Sung by Tom Lehrer, from the 1959 periodic table