资源简介

(共40张PPT)
Copper (Cu)
Electron configuration: 4s13d10 3d10 3d9 3d8
Properties
Malleable and ductile; reddish.
Good conductor of heat and electricity.
Main oxidation state: II
Ores:
Cuprite: Cu2O
Bornite Cu6FeS4
Azurite: Cu3(CO3)2(OH)2
Covellite: CuS
Uses
Electrical wires and switches, plumbing, cooking vessels.
Used as an alloy: brass (Cu/Zn), Bronze (Cu/Sn), Coinage material (Cu/Ni).
Copper sulphate is used widely as an agricultural poison and as an algicide in water purification.
Halides
anhydrous fluoride CuF2 is white, the chloride yellow and the bromide almost black
CuI
Copper(I) oxide, Cu2O
orange-yellow precipitate
Copper(I) chloride, CuCl
white solid, insoluble in water.
Vapor state : dimer of formula Cu2Cl2
concentrated hydrochloric acid
Properties of CuCl
The solid readily dissolves chemically in concentrated hydrochloric acid, forming a complex, and in ammonia as the colorless, linear, complex cation [H3N Cu NH3]+
ammoniacal copper(I) chloride is a good absorber for carbon monoxide, forming CuCl . CO . H2O, and as such is used in gas analysis.
explosive when dry
not in excess)
Copper(l) chloride, bromide and cyanide were used by Sandmeyer
to introduce a chlorine, a bromine atom and a cyanide group
respectively into a benzene ring by addition to the phenyl diazonium
salt.
TESTS FOR COPPER COMPOUNDS
to add hexacyanoferrate(II) (usually as the potassium salt) when a chocolate-brown precipitate of copper(II) hexacyanoferrate(II) is obtained:
chocolate-brown
Inert and Labile Complexes
Complexes in which ligands are rapidly replaced by others are called labile complexes (shorter than 1 min; @ 25 oC, 0.1M)
Slow ---- inert complexes
Labile complexes
All complexes in which the central metal atom contains electrons in eg orbitals
[Ga(C2O4)3]3-, d10; [Cu(H2O)6]2+, d9
[Co(NH3)6]2+,d7 [Ni(H2O)6]2+,d8
[Fe(H2O)6]3+, d5
All complexes that contain less than three d-electrons
[Ti(H2O)6]3+, d1; [V(phen)3]3+, d2
[CaEDTA]2-, d0
Inert Complexes
Octahedral d3 complexes, plus low spin d4, d5 and d6 systems
[Cr(H2O)6]3+,d3
[Fe(CN)6]3-,d5
[Co(NO2)6]3-,d6
[PtCl6]2-,d6
Why
Comparison of the CFSE of a coordination compound and of its activated complex
If the CFSE of the compound is much larger than that of the activated complex, the compound will react slowly
Small fast
Cu Ag Au
Reaction with O2
Au，Ag O2 no reaction，
But if forming precipitate or coordination compound, reaction can happen。
Can not use Cu as NH3 container。
O2
Silverware tarnishes。
Cu,Ag,Au soluble in oxidizing acids。
Ag compounds：
Mostly insoluble
soluble：AgNO3, AgF, AgClO4
insoluble：AgCl, AgBr, AgI, AgCN, AgSCN,
Ag2S, Ag2CO3, Ag2CrO4。
Low thermal stability （light, heat）
color
AgCl AgBr AgI Ag2O Ag2CrO4 Ag2S
white pale yellow dark blood black
yellow brown red
Ag(I) reaction
Silvering mirror reaction：
①
②
③
④
Identification of S2O32-：
)
S(s,
Ag
SO
H
O
H
)
(s,
O
S
Ag
2
4
2
2
3
2
2
b
w
+
+
Relative stability of Ag+ complexes
7
2
3
10
67
.
1
)
)
Ag(NH
(
×
=
+
13
3
=
-
2
3
2
10
9
.
2
)
)
O
Ag(S
(
×
20
2
10
48
.
2
)
Ag(CN)
(
×
=
-
Identification of Ag+
I-
HNO3
Mercury differs from zinc and cadmium in a number of significant ways.
It is used in thermometers, barometers, electrical contacts, and in some types of electrochemical cells. Mercury vapor is used in fluorescent lamps.
Dental amalgam is an alloy of mercury, silver, and tin, and is used for dental restorations.
Long-term exposure to mercury can present a serious health hazard.
Mercury can react with and inactivate sulfur-containing enzymes.
Mercury
Mercury - Hg
Mercury is a heavy, silvery, liquid metal.
Mercury occurs very rarely free in nature, but can be found in ores.
Mercury easily forms alloys with other metals such as gold, silver and tin, which are called amalgams.
Its ease in amalgamating with gold is made use of in recovering gold from its ores.
The metal is widely used in making advertising signs, mercury switches, and other electrical apparatus.
It is used in laboratory work for making thermometers, barometers, diffusion pumps and many other instruments.
Other uses are in pesticides, dental work, batteries and catalysts.
It is a virulent poison, readily absorbed through the respiratory tract, the gastrointestinal tract or through the skin. It is a cumulative poison and dangerous levels are readily attained in air. It is always handled with the utmost care.
Mercury is stable with air and water.
It is a rather poor conductor of heat compared to other metals, and a fair conductor of electricity
Reactions of Hg
2. S2-
1. OH-
If Hg2+ comes from Hg(NO3)2：
HgS -0.758V Hg2S -0.598V Hg
HgS： =1.6×10-52
Therefore：Hg(I) is stable in solution，but disproportionate when precipitate or complex forms。
Aminomercuric chloride
3. Reaction with NH3
In general, all these products are obtained in proportions which depend on the concentrations of NH3 and NH4+ and on the temperature, but more or less pure products can be prepared by suitably
adjusting the conditions
[Hg(NH3)2Cl2], descriptively known as “fusible white precipitate”,
the amide [Hg(NH2)Cl], “infusible white precipitate”
adding will shift eq to right
-
2
4
Nessler
HgI
4
NH
+
reagent，
is
-
I
reaction with I-，SCN-
2
-
2
)
(s,
HgI
2I
Hg
+
+
gold
+
-
2
4
-
2
)
(aq,
HgI
2I
HgI
colorless
2
2
2
-
2
2
Hg
HgI
)
(s,
I
Hg
2I
Hg
+
+
+
green
2
-
O
3H
7I
+
+
2
-
-
2
4
4
)
I(s,
NH
Hg
Hg
4OH
]
2[HgI
NH
+
+
+
brown
O
Can also use HgCl2 to identify Sn2+
Identification of Hg2+
)
(aq,
Hg(SCN)
2SCN
Hg(SCN)
-
2
4
-
2
colorless
+
(s)
Hg(SCN)
2SCN
Hg
2
-
2
+
+
Ruthenium and Osmium
All the platinum group metals are isolated from “platinum concentrates” which are commonly obtained either from “anode slimes” in the electrolytic refining of nickel and copper,
or as “converter matte” from the smelting of sulfide ores.
Preparation of the elements
Ru and Os are usually removed by distillation of their tetroxides immediately after the initial dissolution with hydrochloric acid and chlorine.
Collection of the tetroxides in alcoholic NaOH and aqueous HCl respectively yields OsO2(NH3)4Cl2 and (NH4)3RuCl6 from which the metals are obtained by ignition in H2.
The oxides of ruthenium and
osmium
Oxidation state +8 +4
Ru RuO4 RuO2
Os OsO4 OsO2
Rhodium and Iridium
Pt square planar complexes

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