Ch 24 sec3

24.324.3

The d- and f- block elementnsiss: The d- and f- block elementnsiss: Transistion and Inner Transistion MetalsTransistion and Inner Transistion Metals

OverviewOverview

Most metals come from ores- these are Most metals come from ores- these are minerals which contain metals; minerals which contain metals; metallurgymetallurgy is the process of separating is the process of separating the metals from the ore, there are 3 basic the metals from the ore, there are 3 basic steps: 1) concentrating the oresteps: 1) concentrating the ore

2) chemically reducing the ore to 2) chemically reducing the ore to the metalthe metal

3) refining and purifying the metal3) refining and purifying the metal

Transition ElementsTransition Elements

In the d- blockIn the d- block Most have more than one oxidation stateMost have more than one oxidation state Most have colored aqueous solutionsMost have colored aqueous solutions They have typical metallic properties- They have typical metallic properties-

ductile, malleable, good ocnductors of ductile, malleable, good ocnductors of heat and electricity, lustrous ( silver heat and electricity, lustrous ( silver except Cu and Au)except Cu and Au)

Study table 24.4 for uses of several transition Study table 24.4 for uses of several transition metalsmetals

Notice several are imporant in small amounts Notice several are imporant in small amounts for our healthfor our health

Their reactivity varies: i.e. Sc,Y, La are reactive Their reactivity varies: i.e. Sc,Y, La are reactive like Group 1a elements in water ( although to a like Group 1a elements in water ( although to a lesser degree), whereas Pt and Au are very lesser degree), whereas Pt and Au are very unreactive and resist oxidationunreactive and resist oxidation

Transition ElementsTransition Elements

Titanium, Chromium and Titanium, Chromium and ZincZinc

Ti - low density, strong, corrosion Ti - low density, strong, corrosion resistantresistant

- used in aircraft engines, missiles, - used in aircraft engines, missiles, hip and joint replacement parts; TiOhip and joint replacement parts; TiO2 2 is a is a

white compd used in paint, paper and white compd used in paint, paper and suncsreensuncsreen

- found in the ore “rutile” whichis - found in the ore “rutile” whichis impure TiOimpure TiO2,2, has a wide distribution has a wide distribution

CrCr - relatively rare- relatively rare - corrosion resistant, high luster- corrosion resistant, high luster - used in alloys- stainless steel is 18% Cr; - used in alloys- stainless steel is 18% Cr;

often coats iron and steel objectsoften coats iron and steel objects - has oxidation states of +2,+3, and +6 in - has oxidation states of +2,+3, and +6 in

chromate(CrOchromate(CrO442-2-) and dichromate (Cr) and dichromate (Cr22OO77

2-2-); ); when it has a ox.state of +6 it is a string oxiding when it has a ox.state of +6 it is a string oxiding agentagent


ZincZinc

- obtained from a sulfide ore (sphalerite)n- obtained from a sulfide ore (sphalerite)n

- used widely in industry; produces - used widely in industry; produces galvanized iron (the Zn keeps iron from galvanized iron (the Zn keeps iron from rusting)rusting)

- alloy brass is made of Zn and Cu- alloy brass is made of Zn and Cu

- used as outer case of dry-cell batteries- used as outer case of dry-cell batteries


Iron, Cobalt, NickelIron, Cobalt, Nickel

All 3 have similar properties- including All 3 have similar properties- including magnetismmagnetism

FeFe - 5% of earth’s crust; 2- 5% of earth’s crust; 2ndnd most common most common

metalmetal - cheapest metal- cheapest metal - used to make steel: 2 types carbon - used to make steel: 2 types carbon

steels and alloy steelssteels and alloy steels

FeFe - most steels are carbon steels- which have - most steels are carbon steels- which have

no other metal than iron; can range from mild no other metal than iron; can range from mild steel to high-carbon steel which vary steel to high-carbon steel which vary depending on the amount of C in the steel depending on the amount of C in the steel ( most is 1.5%C)( most is 1.5%C)

- alloy steels contain other transition metals in - alloy steels contain other transition metals in addition to the C: stainless steel tend to have addition to the C: stainless steel tend to have hi % of Cr and Ni in them; stainless steel hi % of Cr and Ni in them; stainless steel resists corrosionresists corrosion


Ni and Co occur in suflide ores (along w/ several Ni and Co occur in suflide ores (along w/ several other trans. metals)other trans. metals)

- used mostly in manufacture of stainless steel - used mostly in manufacture of stainless steel (more ductile, corrosion resistant and tough)(more ductile, corrosion resistant and tough)

- Ni often used to coat iron before it is coated w/Cr- Ni often used to coat iron before it is coated w/Cr - Co-60 is radioactive and used for cancer treatment- Co-60 is radioactive and used for cancer treatment - both are uses as catalysts in industrial processes- both are uses as catalysts in industrial processes - Monel metal is a an alloy of Ni and Cu used in boat - Monel metal is a an alloy of Ni and Cu used in boat

propeller shaftspropeller shafts


Copper, Silver, GoldCopper, Silver, Gold

All 3 can occur in a free stateAll 3 can occur in a free state Called “coinage metals”Called “coinage metals” Have low chemical reactivityHave low chemical reactivity CuCu - - found in the ores chalcopyrite found in the ores chalcopyrite

( CuFeS( CuFeS22); chalcocite); chalcocite (Cu(Cu22S) and cuprite S) and cuprite (Cu(Cu22O)O)

- processed using electrolytic refining- processed using electrolytic refining

CuCu - used for electrical wiring (only Ag is a - used for electrical wiring (only Ag is a

better conductor)better conductor) - used in plumbing- used in plumbing - brass is an alloy of Cu and Zn; bronze - brass is an alloy of Cu and Zn; bronze

is an alloy made of Cu and Sn ( earliest is an alloy made of Cu and Sn ( earliest known alloys)-uses include marine known alloys)-uses include marine equip., decorative arts, pipes, nozzlesequip., decorative arts, pipes, nozzles


AgAg

- - occurs freely and in ore argentite (Agoccurs freely and in ore argentite (Ag22S)S)

- usually obtained when other metals get - usually obtained when other metals get refined refined

- good light reflector and can be used to coat - good light reflector and can be used to coat the back of mirrorsthe back of mirrors

- excellent conductor of heat and electricity- excellent conductor of heat and electricity

- - silver halides are used in film developingsilver halides are used in film developing


AgAg

- tarnishes easily ( tarnish is Ag- tarnishes easily ( tarnish is Ag22S)- redox reaction w/ S)- redox reaction w/ HH22S)S)

AuAu - recovered in free form, also as product of Cu refining- recovered in free form, also as product of Cu refining- Most malleable and ductile of metalsMost malleable and ductile of metals- Used for jewelery and in gold-leaf applicationsUsed for jewelery and in gold-leaf applications- High tech industry uses it to coat circuits because it is High tech industry uses it to coat circuits because it is

so corrosion resistantso corrosion resistant


AuAu - also used in dentistry and to treat - also used in dentistry and to treat

arthritisarthritis - pure gold is very soft; often alloyed to - pure gold is very soft; often alloyed to

make it harder: 24 karat is 100% goldmake it harder: 24 karat is 100% gold 22 karat is 22/24 x 100= 92% gold22 karat is 22/24 x 100= 92% gold -white gold is an alloy of gold,nickel -white gold is an alloy of gold,nickel

and other metalsand other metals


Lanthanides and Lanthanides and ActinidesActinides

Inner transistion metals; in f- blockInner transistion metals; in f- block Called rare earth metals, although they Called rare earth metals, although they

are not as rare as first thoughtare not as rare as first thought Lanthanides are silvery, high melting ptsLanthanides are silvery, high melting pts Some of the lantanide oxides are used in Some of the lantanide oxides are used in

sunglasses, welders goggles, and sunglasses, welders goggles, and camera lensescamera lenses

ActinidesActinides

- all radioactive and have similar - all radioactive and have similar chemical propertieschemical properties

- those whose atomic number is greater - those whose atomic number is greater than 92 are called the transuranium than 92 are called the transuranium elements and are made in particle elements and are made in particle acceleratorsaccelerators

Lanthanides and Lanthanides and ActinidesActinides

Education

Ch 24 sec3