大学化学无机化学双语教学课件PPT-Chapter17 Halogen

Basic characteristic
F
Configuration of valence electrons
Main oxidation number
-1
Dissociation energy/kJ·mol
solubility/g/100mgH2O Atomic radius/pm
X- ionic radius/pm
330.5 301.7
2.98 -334.7
2．66 -292.9
1.08 0.535
Existence：Halogen is in the form of chemical compound.
F: C五存a位5F在。(PO于4)3萤在地石壳Ca中F2的、质冰量晶百分石含N量a3A约lF06.0、15%氟，磷占灰第石十
1. Reaction with metal
F2 ：① It directly combines with metal into the highest oxidation state of fluoride，which reaction progress is often violent with flaming and exploding.
First ionization energy/kJ·mol-1 First electron affinity energy /kJ·mol-
157.7 分解水
71 136 1861.0
338.8
electronegativity (Pauling)
X-hydration heat/kJ·mol-1
53.53 85.01
158
Cl2
gas百度文库
yellow green
172.17
239.18
242
Br2
liqui d
reddish brown
265.9 331.93
193
I2
solid
atropurpu reus
386.7
457.5
151
F2 Cl2 Br2 I2
state： gas
solid
Iodine heated sublimate and starch turns blue with iodine.
brownish red.
The color iodine dissolves in CCl4 or CS2 is purple. Existence is in the form of molecule.
The color iodine dissolves in ether and ethanol is brown.
2－1 Halogen element
一、Halogen element of physical property
halogen element
state
color
fusion
boiling
dissociation energy
point (K) point (K) (kJ/mol)
F2
gas
light yellow
Electrode potentialφØ (X2/X)/V
3.98 -506.3 2.87
Cl
Br
I
ns 2np 5
-1,+1,+3,+5,+7
238.1 189.1 148.9
0.732 3.58 0.029
99
114
133
181
195
216
1251.1 1139.9 1008.4
354.8 3.16 -368.2 1.36
I： 碘在海水中存在的更少，碘主要被海藻所吸收，海水 中碘的含量仅为5%, 碘也存在于某些盐井盐湖中，南 美洲智利硝石含有少许的碘酸钠。
§17－2 Halogen element and
chemical compound
2－1 Simple halogen substance
2－2 Halide compound
Antibonding orbital energy difference in halogen’s π* and σ* decreases with Z increasing.
solution：
The color change bromine dissolves in ethanol，ether， trichloromethane，tetrachloromethane is from yellow to
fusion and boiling point ： up
color： light
dark
dissociation energy：
F2 （anomaly） ？
Cl2 > Br2 > I2
( 2 px )2 ( 2 p
)
4
(
2
p
)4
( 2 px ) 2 ( 2 p
)
4
(
2
p
)3 ( * )1 2 px
Chapter 17 Halogen
§17－1 Halogen
氟 ( Fluorine) 溴 ( Bromine) 砹 ( Astatine)
氯 ( Chlorine) 碘 ( Iodine)
Halogen locate in VIIA periodic table of the elements, which valence shell structure is ns2np5 .
forming a solvent compound The solubility iodine dissolves in KI or other iodide is more
than in water.
I2
I
I 3
Polyiodide’s property（KI3 ）is similar to iodine.
二、halogen element of physical property
electrode potential： X2 2e 2 X
X2/X
(V)
F2 2.87
Cl 2 1.36
Br2 1.065
I2 0.535
X2 oxidability X－ reducibility
Except I2 , both X2 are strong oxidant. They can react with metal and nonmetal.
Cl: 主要存在于海水、盐湖、盐井，盐床中，主要有钾石 盐1.9K%C，l 、地光壳卤中石的质K量Cl百·M分gC含l2量.6H02.0O3。1%海，水占中第大十约一含位氯。
Br: 主要存在于海水中，海水中溴的含量相当于氯的 1/300，盐湖和盐井中也存在少许的溴，地壳中的质量 百分含量约1.6 %.