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  • 1. 24.3 The d- and f- block elementnsiss: Transistion and Inner Transistion Metals
  • 2. Overview
    • Most metals come from ores- these are minerals which contain metals; metallurgy is the process of separating the metals from the ore, there are 3 basic steps: 1) concentrating the ore
    • 2) chemically reducing the ore to the metal
    • 3) refining and purifying the metal
  • 3. Transition Elements
    • In the d- block
    • Most have more than one oxidation state
    • Most have colored aqueous solutions
    • They have typical metallic properties- ductile, malleable, good ocnductors of heat and electricity, lustrous ( silver except Cu and Au)
  • 4.
    • Study table 24.4 for uses of several transition metals
    • Notice several are imporant in small amounts for our health
    • Their reactivity varies: i.e. Sc,Y, La are reactive like Group 1a elements in water ( although to a lesser degree), whereas Pt and Au are very unreactive and resist oxidation
    Transition Elements
  • 5. Titanium, Chromium and Zinc
    • Ti - low density, strong, corrosion resistant
    • - used in aircraft engines, missiles, hip and joint replacement parts; TiO 2 is a white compd used in paint, paper and suncsreen
    • - found in the ore “rutile” whichis impure TiO 2, has a wide distribution
  • 6.
    • Cr
    • - relatively rare
    • - corrosion resistant, high luster
    • - used in alloys- stainless steel is 18% Cr; often coats iron and steel objects
    • - has oxidation states of +2,+3, and +6 in chromate(CrO 4 2- ) and dichromate (Cr 2 O 7 2- ); when it has a ox.state of +6 it is a string oxiding agent
    Titanium, Chromium and Zinc
  • 7.
    • Zinc
    • - obtained from a sulfide ore (sphalerite)n
    • - used widely in industry; produces galvanized iron (the Zn keeps iron from rusting)
    • - alloy brass is made of Zn and Cu
    • - used as outer case of dry-cell batteries
    Titanium, Chromium and Zinc
  • 8. Iron, Cobalt, Nickel
    • All 3 have similar properties- including magnetism
    • Fe
    • - 5% of earth’s crust; 2 nd most common metal
    • - cheapest metal
    • - used to make steel: 2 types carbon steels and alloy steels
  • 9.
    • Fe
    • - most steels are carbon steels- which have no other metal than iron; can range from mild steel to high-carbon steel which vary depending on the amount of C in the steel ( most is 1.5%C)
    • - alloy steels contain other transition metals in addition to the C: stainless steel tend to have hi % of Cr and Ni in them; stainless steel resists corrosion
    Iron, Cobalt, Nickel
  • 10.
    • Ni and Co occur in suflide ores (along w/ several other trans. metals)
    • - used mostly in manufacture of stainless steel (more ductile, corrosion resistant and tough)
    • - Ni often used to coat iron before it is coated w/Cr
    • - Co-60 is radioactive and used for cancer treatment
    • - both are uses as catalysts in industrial processes
    • - Monel metal is a an alloy of Ni and Cu used in boat propeller shafts
    Iron, Cobalt, Nickel
  • 11. Copper, Silver, Gold
    • All 3 can occur in a free state
    • Called “coinage metals”
    • Have low chemical reactivity
    • Cu
    • - found in the ores chalcopyrite ( CuFeS 2 ); chalcocite (Cu 2 S) and cuprite (Cu 2 O)
    • - processed using electrolytic refining
  • 12.
    • Cu
    • - used for electrical wiring (only Ag is a better conductor)
    • - used in plumbing
    • - brass is an alloy of Cu and Zn; bronze is an alloy made of Cu and Sn ( earliest known alloys)-uses include marine equip., decorative arts, pipes, nozzles
    Copper, Silver, Gold
  • 13.
    • Ag
    • - occurs freely and in ore argentite (Ag 2 S)
    • - usually obtained when other metals get refined
    • - good light reflector and can be used to coat the back of mirrors
    • - excellent conductor of heat and electricity
    • - silver halides are used in film developing
    Copper, Silver, Gold
  • 14.
    • Ag
    • - tarnishes easily ( tarnish is Ag 2 S)- redox reaction w/ H 2 S)
    • Au
    • - recovered in free form, also as product of Cu refining
    • Most malleable and ductile of metals
    • Used for jewelery and in gold-leaf applications
    • High tech industry uses it to coat circuits because it is so corrosion resistant
    Copper, Silver, Gold
  • 15.
    • Au
    • - also used in dentistry and to treat arthritis
    • - pure gold is very soft; often alloyed to make it harder: 24 karat is 100% gold
    • 22 karat is 22/24 x 100= 92% gold
    • -white gold is an alloy of gold,nickel and other metals
    Copper, Silver, Gold
  • 16. Lanthanides and Actinides
    • Inner transistion metals; in f- block
    • Called rare earth metals, although they are not as rare as first thought
    • Lanthanides are silvery, high melting pts
    • Some of the lantanide oxides are used in sunglasses, welders goggles, and camera lenses
  • 17.
    • Actinides
    • - all radioactive and have similar chemical properties
    • - those whose atomic number is greater than 92 are called the transuranium elements and are made in particle accelerators
    Lanthanides and Actinides

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