Download INERT METALS Properties Copper Silver Gold Earth`s crust

INERT METALS
Properties
Copper
Silver
-3
6.8x10
Earth`s crust
abundance
Electron
configuration
10
8x10
1
Gold
-6
-7
3.1x10
10
1
14
10
[Ar]3d 4s
[Kr]4d 5s
[Xe]4f 5d 6s
1084.6
961
1064.2
2927
2162
2856
Density
8.92
10.5
19.3
Common oxidation
num.
+1, +2
1
+1, +3
Physical State
solid
solid
solid
Color
metallicreddish
metallicsilver
bright yellow
o
Melting point ( C)
o
Boiling point ( C)
Properties
Earth`s crust abundance
Mercury
-6
6.7x10
Electron configuration
[Xe]4f 5d 6s
o
Melting point ( C)
o
Boiling point ( C)
Density
Common oxidation num.
Physical State
Color
14
Platinum
-6
3.7x10
10
2
14
9
1
[Xe]4f 5d 6s
-38.8
1768.3
356.7
3825
13.6
+1, +2
liquid
silvery white
21.1
+2, +4
solid
greyish white
Introduction
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Inert metals are Cu, Hg, Ag, Pt, Au, Bi, Pd, Os, Ir, Ru and Rh.
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These metals have no tendency to have an ionic structure.
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They have very high density.
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They are found in nature as pure metals.
Copper, Cu
Introduction
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First metal to be used by humans.
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Second most consumed metal, after iron.
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Found first in Cyprus.
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Cuprum means the “Island of Cyprus” in Latin.
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Very soft metal with a characteristic.
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Lightest inert metal.
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Second best conductor of electricity after Ag.
1. Occurrence
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The most important copper minerals are Chalcopyrite
(copper pyrite), CuFeS2, Chalcocite, Cu2S, Agurite,
CuCO3.Cu(OH)2, Cuprite, Cu2O, Malachite, CuCO3.Cu(OH)2.
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In the preparation of Cu CuFeS2 is used.
2CuFeS2 + 4O2 → Cu2S + 3SO2 + 2FeO(s)
3Cu2S + 3O2 → 6Cu(s) + 3SO2
1
2. Chemical Properties
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Less active metal than hydrogen.
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No reaction with H2O, HCI, dil. H2SO4.
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HNO3 and conc. H2SO4react with copper.
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Hot copper reacts with all of the halogens.
Cu + Cl2→CuCl2
(at low temperature)
2Cu + Cl2→2CuCl (at high temperature)
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O2 and S produce oxides and sulfides.
2Cu + O2→ 2CuO (below 1000°C)
4Cu + O2→ 2Cu2O (above 1000°C)
Cu + S →CuS
(below 1000°C)
2Cu + S → Cu2S (above 1000°C)
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Copper displaces less reactive metals.
Cu + 2AgNO3 → Cu(NO3)2 + 2Ag
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Copper reacts with oxidizing acids.
2Cu + 4HNO3(dil.) + O2→ 2Cu(NO3)2 + 2H2O
2Cu + 2H2SO4 (dil.) + O2→ 2CuSO4 + 2H2O
3. Compounds
+1
+2
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Cu ion is called cuprous, Fe is cupric.
+1
+2
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Cu compounds are stable at high temperature but Cu
compounds are stable at low temperatures.
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The most important cuprous compounds are Cu2O and
CuCl. And Cupric compounds are CuCl2 and CuSO4.
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When CuSO4.5H2O is heated CuSO4 is formed.
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Cu alloys are brass (Zn-Cu), bronze (Cu-Zn-Sn) and
aluminum bronze (Cu-Al).
Uses
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Cu2O is used to produce red colored glass.
CuCl2 gives a green color in fireworks.
In mirrors to reflect infrared rays.
Strong alloys with gold.
Wire and plates.
As a pigment.
Silver, Ag
Introduction
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It is used since ancient times.
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Latin word “argentum” means silver.
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Second metal after gold in malleability.
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It has the highest electrical conductivity of any element
and has the highest thermal conductivity of any metal.
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It is a precious metal.
1. Occurrence
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It is found as metallic form or in its minerals.
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The most important silver minerals are Argentite or silver
glance, Ag2S, Pyrangyrite or Ruby silver, Ag3SbS3, Silverarsenic glance, Ag3AsSi3, and Home silver, AgCl.
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There are different methods to get pure silver;
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Amalgam method:
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Hg is added the ore containing free silver.
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By distilling this mixture, Hg is evaporated.
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Silver remains in the container.
Cyanide method:
Ag2S + 4NaCN → 2NaAg(CN)2 + Na2SO4
Zn + 2NaAg(CN)2 → Na2Zn(CN)4 + 2Ag
2. Chemical Properties
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No reaction with acids and do not have oxidizing property.
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Reacts with oxidizing acids without producing hydrogen
gas.
3. Compounds
Silver Nitrate, AgNO3
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Colorless and crystalline salt.
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Very soluble in water
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It is obtained by the reaction;
3Ag(s) + 4HNO3(dil.) → 3AgNO3 + NO(g) +2H2O
Ag(s) + 2HNO3 → AgNO3 + NO2 + H2O
Uses
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In the chemical industry.
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An excellent catalyst.
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As jewelry and cutlery.
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In industrial alcohol production.
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In production of fertilizers with NH3.
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AgI compounds for “seeding” clouds.
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Wire and plates for repairing broken limbs.
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In medicine, surgeons’ instruments, tooth fillings,
photography, batteries.
Gold, Au
Introduction
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The most malleable and ductile metal.
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It is yellow and soft metal.
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Purity of gold is expressed in karats.
Karats
24
22
18
% fine Gold
100
91.8
75
14
59
1. Occurrence
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It is found in nature in elemental form.
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Important gold minerals are Calavarite, AuTe2, Silvanite,
AuAgTe4.
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In the preparation of pure gold;
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Impure gold is dissolved in aqua regia.
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Obtained solution is evaporated.
HAuCl4.4H2O is formed.
HAuCl4(heat) → AuCl3 + HCl
AuCl3 (heat) → AuCl + Cl2
2AuCl (heat) → 2Au + Cl2
2. Chemical Properties
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It has no reaction with single acid or by bases.
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Dissolves readily in aqua regia.
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Very inactive metal.
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Reaction of gold with aqua regia, king water.
Au + HNO3 + 3HCl → HAuCl4 + NO + 2H2O
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Reaction with F2, Cl2 and Br2, by forming water soluble
gold (III) halides.
2Au + 3X2 → 2AuX3
(X = F, Cl and Br)
3. Compounds
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Gold forms Au2O and Au2O3 oxides and hydroxide, AuOH.
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All compounds of gold are decomposed by heating.
Uses
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Money transfer between banks and treasuries.
Coating metals to prevent corrosion.
In connections of electrical circuits.
Good conductor in transistors.
In jewellery industry.
Filling teeth.
Mercury, Hg
Introduction
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It is only the liquid metal at room temperature.
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In Latin, ‘mercury’ means liquid silver.
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Form alloys with all metals except Fe and Pt.
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Liquid or solid form conducts electricity.
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Its vapor is very toxic.
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Mercury alloys are called amalgams, Ag-Hg, Cd-Hg.
1. Occurrence
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Found on the surface of rocks in elemental form and as the
alloys of Ag and Au.
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The most abundant Hg mineral,HgS is called as cinnabar.
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In the preparation of mercury Cinnabar is used.
HgS + O2 → Hg + SO2
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Heating HgS in the presence of CaO.
4HgS + 4CaO → 4Hg + 3CaS + CaSO4
2. Chemical Properties
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No hydrogen gas after reaction with acids.
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Forms its oxides in trace amount in air.
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Stable in air
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No reaction with H2O, HCl and dil. H2SO4
Hg + H2SO4 → HgSO4 + SO2 + 2H2O
Hg + 4HNO3(conc.) → Hg(NO3)2 + 2NO2 + 2H2O
3Hg + 4HNO3(dil.) → 3HgNO3 + NO + 2H2O3.
3. Compounds
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HgO is a yellow-orange powder.
2Hg + O2 → 2HgO
HgCl2+2NaOH → HgO+ 2NaCl + H2O
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The obtained HgO decomposes by heating
HgO(s) → Hg(l) + 1/2O2
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The most important halides of mercury are HgCl2 and
Hg2Cl2.
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HgCl2 + Hg → Hg2Cl2
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Hg compounds are called mercurous.
2+
Hg compounds are called mercuric.
Hg(NO3)2 and HgS are also important compounds of
mercury.
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Uses
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Amalgams for filling teeth in dentistry.
HgCl is used as an insecticide.
In production of batteries.
In thermometers.
In barometers.
Platinum, Pt
Introduction
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Spanish scientist Antonio de Wloa found platinum in 1735.
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Platina means platinum in Spanish .
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White , malleable and very ductile.
1. Occurrence
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It is generally found in elemental form, can also be found
as compounds like PtAs2, sperilite.
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It is also found in copper-nickel salts.
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In laboratories it is prepared by heating of ammonium
salts.
(NH4)2PtCl6 → Pt + 2NH4Cl + 2Cl2↑
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Platinum is an extremely rare metal.
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Platinum is often found chemically uncombined as native
platinum.
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It is found with some other metals, Tellurides, sulfides,
antimonides and arsenides
2. Reactions
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No reaction with acids, bases and water.
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It becomes more active when heated
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Reacts with some nonmetals.
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If it is oxidized,platinum(II)oxide PtO forms.
2Pt + O2 → 2PtO
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It can react only with king water.
3Pt + 18HCl(conc.) + 4HNO3(conc.) → 3H2PtCl6 + 4NO +
8H2O
Pt + 2F2 → PtF4
Pt + 2Cl2 → PtCl4
3. Compounds
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Important platinum compounds are Platinum (IV) fluoride,
PtF4, Platinum (IV) chloride, PtCl4, and Hexa chloro
platinate acid, H2PtCl6.
Uses
In the production of medical instruments.
As a catalyst in most organic reactions.
For preparation of very thin plates.
Pt wires for constructing high temperature electric
furnaces.
For coating jet engine fuel nozzles, missile nose cones.
For oxidation of NH3 to NO.
In filling teeth, In jewelry.