The Elements

1
The Elements

• Representative and Transition Elements
• Section 15-1 and 15-2

2
Groups 1 and 2

• Always found in nature combined with other
  elements
• Active metals
• Readiness to form new substances
• All metals except hydrogen

3
Alkali Metals

• Silvery solids
• Low densities
• Low melting points
• Increase in reactivity as you move from top to
  bottom
• Most reactive is Francium

4
Alkali Metals

• Uses
• Lithiumbatteries
• Sodiumtable salt
• Sodium and Potassiumdietary requirements

5
Alkali Earth Metals

• Each is denser, harder, and has a higher melting
  point than the alkali metal in same period
• Reactive, but not as reactive as alkali metals

6
Alkali Earth Metals

• Uses
• Berylliumfound in gems emerald and aquamarine
• Magnesiumfound in chlorophyll of green plants

7
Groups 13 thru 18

• Not all solid metals
• A single group can contain metals, nonmetals, and
  metalloids
• A single group can also have members that are
  solids, liquids, and gases

8
Group 13Boron Family

• All metals except boron (brittle, black
  metalloid)
• Used to make a variety of products
• Cookwareboron
• Soft-drink cansaluminum
• Computer chips--gallium

9
Group 14Carbon Group

• Carbonnonmetal
• Diamond and graphite
• Found in all living things
• Silicon Germaniummetalloid
• Semiconductors
• Computer chips
• Tin Lead
• Two heaviest elements in group
• Leadx-ray aprons, car batteries
• Tinpewter, toothpaste, coating for steel cans

10
Group 15The Nitrogen Group

• Nitrogen Phosphorus
• Nonmetals
• Required by living things
• Part of DNA
• Nitrogen
• 80 of air you breathe
• Get nitrogen for body from eating plants
• Phosphorus
• White phosphoruscant be exposed to airit will
  explode !!
• Red phosphorusused for head of matches
• Also needed for healthy teeth and bones

11
Group 16the Oxygen Family

• Oxygen
• 20 of Earths atmosphere
• Required for combustion
• Ozone shields organisms from radiation
• Sulfur
• Solid, yellow nonmetal
• Used to make sulfuric acid
• Paint, fertilizer, detergent, rubber
• Selenium
• Conducts electricity when exposed to light
• Used in solar cells, photographic materials

12
Group 17The Halogen Group

• All metals except for astatine (radioactive
  metalloid)
• Means salt-former
• Example, table saltsodium chloride
• Most reactive is fluorine
• Least reactive is iodine

13
Group 18The Noble Gases

• Rarely combine with other elements
• Great for signs
• Each glows a different color light when
  electricity is passed through
• Helium
• Less dense than air
• Great for balloons
• Argon
• Most abundant
• Krypton
• Used to illuminate landing strips
• Radon
• Radioactive produced naturally
• Harmful can cause lung cancer

14
Transition Elements

• Groups 3-12
• All metals
• Most found combined with other elements in ores
• Few found as pure elements (gold and silver)

15
Iron Triad

• Elements in period 4
• Iron, cobalt, nickel
• Have magnetic properties
• Industrial magnetsalloy of nickel, cobalt,
  aluminum
• Nickel used in batteries
• Iron is necessary in hemoglobin to transport
  oxygen in body
• Iron also combined with other metals to produce
  steel

16
Uses of Transition Elements

• Tungstenhighest melting point of any metal
• Used as filament in light bulbs
• Mercurylowest melting point
• Used in thermometers and barometers
• Only metal liquid at room temperature
• Poisonous to living things

17
Uses of Transition Elements

• Chromiumcomes from Greek word for color, chroma
• Used in paints
• Platinum group
• Ruthenium, rhodium, palladium, osmium, iridium,
  and platinum
• Can be used as catalysts
• Used to produce electronics

18
Lanthanides

• Also called rare earth elements
• Usually found in combination with oxygen in
  Earths crust
• Soft metals than can be cut with a knife

19
Actinides

• All radioactive
• Thorium, protactinium, uranium are only ones
  found naturally on Earth
• Plutoniumused to fuel nuclear power plants
• Americiumused in smoke detectors
• Californium-252used to kill cancer cells