基础化学
主讲人： Xiuli Dong
董秀丽 副教授
Office ：实验楼 B 楼 213
Tel ： 6913464 QQ: 850961018

 Xiuli Dong
董秀丽
(15h, 3 weeks )
 Wei Hu
胡威
(15h, 3 weeks )
 Xiaoyan Wang
王晓艳
(10h, 2 weeks )
 Yuling Huang
黄玉玲
(10h, 2 weeks )
 Huaibin Zhang
张怀斌
(10h, 2 weeks )

 Language: English and Chinese
 Question anytime and anywhere
 Method: memorize based on understanding
 Notice: focal points
 Exercises:

1. the Textbook

2. the main contents
Atomic
Structure
Osmotic
Pressure of
Solutions
Electrolyt e
Solutions
Basic chemistry
Buffer
Solutions
Coordinatio n Complexes
Molecular
Structure
Rates and
Mechanisms of Chemical
Reactions
Organic chemistry

3. Course Schedule for Basic Chemistry

1.1 Introduce to Chemistry
1.2 Measurement and SI Units
1.3 Ways of Expressing Concentration
1.4 Names and Symbols of the Elements
1.5 Nomenclature Inorganic Compounds
Key points: Express the concentration of a solution in several different ways (such as molarity , molality, mole fraction )

1.1.1 What is chemistry?
 Term:
 The dictionary defines chemistry as "the science of the composition, structure, properties, and reactions of matter, especially of atomic and
 molecular systems."
Chemistry is the study of matter and its interactions with other matter and with energy.

2. Why do we study chemistry?
 Every material thing is a chemical or a mixture of chemicals.
 Chemistry is central to all branches of science.
Specialized steels in bicycles
Liquid crystals in computer screens
High-tension polymers in synthetic hip joints

Ronald Breslow:
Chemistry Today and Tomorrow—The
Central, Useful, and Creative Science
Considering the importance of chemistry for understanding life, and the importance of medicinal chemistry for health, it is no surprise that the normal education of physicians involves a lot of chemistry. … Modern doctors need to prepare for a future in which chemistry plays an even larger
R. Breslow is Professor of Chemistry at
Columbia University and the President of the American
Chemical Society.
role in human health.

1.4 Names and Symbols of the Elements

6.
7.
4.
5.
8.
9.
10.
1.
2.
3.
Hydrogen H 1.00794
Helium He 4.002602
Lithium Li 6.941
Beryllium Be 9.012182
Boron B 10.811
Carbon C 12.011
Nitrogen N
Oxygen O
14.00674
15.9994
Fluorine F 18.9084032
Neon Ne 20.1797

11.
12.
13.
14.
15.
16.
17.
18.
Sodium Na
Magnesium Mg
22.989768
24.3050
Aluminum Al 26.98l539
Silicon Si 28.0855
Phosphorus P 30.973762
Sulfur S
Chlorine Cl
32.066
35.4527
Argon Ar 39.948

19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
Potassium K 39.0983
Calcium Ca 40.078
Scandium Sc 44.955910
Titanium Ti 47.88
Vanadium V 50.9415
Chromium Cr 51.9961
Manganese Mn 54.93805
Iron Fe 55.845
Cobalt Co 58.93320
Nickel Ni 58.6934

29.
Copper Cu 63.546
30.
Zinc Zn 65.39
31.
Gallium Ga 69.723
32.
Germanium Ge 72.61
33.
Arsenic As 74.92l59
34.
Selenium Se 78.96
35.
Bromine Br 79.904
36.
Krypton Kr 83.80

 Units are standards that are used for quantitative comparison between measurements for the same type of quantity.
 The first measurements were probably based on the human body.
 In 17th and 18th centuries, scientists found that the lack of standard units was a problem.

 Our current system of measurement, the metric system, began in 1790 when the National Assembly of France set up a committee to establish consistent unit standards.
 In 1960, another international committee met in
France to establish the International System of
Units, a revised metric system now accepted by scientists throughout the world.
 The units of this system are called SI units, from the French Système International d'Unités.

 The SI system is based on a set of 7 fundamental units, or base units , each of which is identified with a physical quantity.
 All other units, called derived units , are combinations of these seven base units. For example, the unit for speed, meters per second
(m/s), is the unit for length (m) divided by the unit for time (s).
 For quantities that are much smaller or much larger than the base unit, we use decimal prefixes and scientific notation ( A × 10 n ).

1.3.1 SI Base Units and SI Prefixes
Table 1 SI Base Units
Quantity
Length
Mass
Time
Temperature
Unit meter kilogram
Symbol Chinese m 米 kg 千克 second s 秒 kelvin K 开尔文
Amount of substance mole mol 摩尔
Electric current ampere A 安培
Luminous intensity candela cd 坎德拉

1.3.2 SI Base Units and SI Prefixes
Table 2 SI Prefixes
Multiple Prefix Symbol Multiple Prefix Symbol
10 18
10 15
10 12
10 9
10 6
10 3
10 2
10 exa E peta P tera T giga G mega M kilo k hecto h deka da
10 -1
10 -2
10 -3
10 -6
10 -9
10 -12
10 -15
10 -18 deci d centi c milli m micro μ nano n pico p femto f atto a
For example: km
、 m
、 dm
、 cm
、 mm
、 μm 、 nm
； s
、 ps
、 fs
千米、米、分米、厘米、毫米、微米、纳米；秒、皮米、飞米

1.3.3 Some Important SI Units in Chemistry
Length and Mass
 The meter (m) is the SI base unit of length. By combining it with one of the SI prefixes, you can get a unit of appropriate for any length measurement. the nanometer (nm): 1nm=10
–9 m
 The kilogram (kg) is the SI base unit of mass. In forming other SI mass units, prefixes are added to the word gram (g) to give units such as the milligram ( 1mg=10
–3 g ).

Volume (derived unit):
 Volume is the space that a given quantity of matter
 occupies.
The SI unit for volume is the cubic meter (m 3 ).
Since this is a rather large volume for typical laboratory situations, the metric unit, known as the liter , is used.
 One liter is defined as the exact volume of one cubic decimeter (i.e. 1 L = 1 dm 3 = 10
–3 m 3 ).
 On a smaller scale, one milliliter is the exact volume of one cubic centimeter
(1 mL = 1 cm 3 = 1 cc = 10
–6 m 3 ).

Temperature (derived unit):
 The Celsius scale is defined by assigning the freezing point of water a value of 0℃ and the boiling point of water as 100℃. （摄氏温度）
 The relationship between Celsius and Kelvin temperature is
T
K
= T
C
+ 273.15
T = t + 273.15
开尔文温度 = 摄氏温度 + 273.15
Copyright© by Houghton Mifflin Company. All rights reserved.
10







 solution 溶液 solute 溶质 solvent 溶剂 dissolve 溶解 dilute 稀的 concentrated 浓的 concentration 浓度







 mole 摩尔 liter 升 milliliter 毫升 molar mass 摩尔质量 amount of substance 物
质的量 molarity 物质的量浓度 molality 质量摩尔浓度 mole fraction 摩尔分数

（溶液的组成标度）
The concentration of a solute is the amount of
solute dissolved in a given quantity of solvent
or solution.
The quantity of solvent or solution can be expressed in terms of volume or in terms of
mass or molar amount .
Thus, there are several ways of expressing the concentration of a solution, such as
molarity, molality and mole fraction.

1.4.1 The Mole Concept
1.4.1.1 mol （ 摩尔 ）
 Definition: The mole is the SI unit for amount of substance. It is defined as the quantity of a given substance that contains as many entities
(molecules or formula units) as the number of
atoms in exactly 12 g of carbon-12. This number is called Avogadro’s number and has a value of 6.02
× 10 23 units/mol .
1 mol=12g of 12 C=6.02
× 10 23 units

 Notice: When using the term mole, it is important to specify the formula of unit to avoid any misunderstanding.
 For example,
1 mol H contains 6.02
× 10 23 H atoms .
1 mol H + contains 6.02
× 10 23 H ions.
1 mol H
2 contains 6.02
× 10 23 H
2 molecules .
1 mol H
2
---------- 2 mol H
1 mol H
2
SO
4
---------- 2 mol H +
---------- 1 mol SO
4
2-

Problems

For example,
98 grams of H
2
SO
4 is equivalent to one mole of
H
2
SO
4
, we can write the following relationship:
98 g H
2
SO
4

1 mol H
2
SO
4
49 grams of H
2
SO
4 is equivalent to 0.5 mole of
H
2
SO
4
, we can write the following relationship:
49 g H
2
SO
4

0 .
5 mol H
2
SO
4

1.4.1.2 Molar mass ( 摩尔质量 )

Definition: The molar mass of any substance is the mass (in gram) of one mole of that substance.
mass kg, g
Molar mass kg •mol -1 , g •mol -1
M
B def m
B
/ n
B
Mole mol

Conclusion: For all substances, the molar mass in grams per mole equal to the formula weight in atomic mass grams.
Molar mass = Formula weight


Interconverting Moles and Mass:
Example 1 Conversion of Mass to Mole
(a)How many moles of NaOH are present in 80g?
(b)How many moles of O
2 are present in 16g?
(c)How many moles of O are present in 16g?
Procedure

Write down what you have been given.

Find the molar mass (molecular weight ) of the molecule.

Calculate the moles of the molecule.
n
NaOH m
NaOH
/M
NaOH
80 / 40 2 mol

1.4.2 Molarity- Molar Concentration
( 摩尔浓度，物质的量浓度 )
Definition: The molarity of a solution is the moles of solute in a liter of solution.
M
 moles liters of of solute solution
 n
V ( L )
Mole of the sulute , mol
Molarity mol•m -3 , mol•L -1 , mmol•L -1 ,μmol•L -1 c
B def n
B
/ V
Volume of the sulution m 3 , L
c(C
6
H
12
O
6
) = 3.9 mmol•L -1 ~ 5.6 mmol•L -1

Example2 Calculating Molarity of a Solution
What is the molarity of a solution prepared by dissolved 4.5 g of NaCl in enough water to form 500 mL of solution?
Procedure

Write down the formula for molarity and what you have been given .

Convert the mass of solute to moles of solute by using the molar mass.

Calculate the molarity .
n c
NaCl
NaCl m
NaCl
/M
NaCl
4.5 / 58.5 0.077 mol n
NaCl
/V
0.077 / 0.500 0.154 mol•L -1

 Dilution of Concentrated Solution
When a solution is diluted, the volume is increased by adding more solvent and the concentration is decreased, but the total amount of solute is constant.
c c
·V c
= c d
·V d
= n
Example 3 Calculation of Molarity of a Dilute Solution
What is the molarity of a solution of KCl that is prepared by dilution of 855 mL of a 0.475 mol•L -1 solution to a volume of 1.25 L?
c d c c
·V c
/
V d
0.475*0.855 / 1.25 0.325 mol•L -1

 Conversion of Mass Percent of Solute to Molarity
Mass percent%
 mass mass of of solute solution
(g)
(g)

100%
Example 4 Calculation of Molarity from Mass Percent
Concentrated laboratory acid is 35.0% by mass HC1 and has a density of 1.18 g/mL. What is its molarity?
Conclusion: c
 density

1000
 m asspercent molar mass

 
1000

%
M

1 .
18

1000

35 .
0 %
36.5

11 .
3 mol

L

1

Procedure

You can get mass of solute in 100 g of solution using definition of mass percent.

Convert the mass of solution to volume of solution by using the density.

Convert the mass of solute to moles of solute by using the molar mass.
 Write down the formula for molarity and what you have been given .

Calculate the molarity .

( 稀溶液的依数性 )
Introduction
Solution
Injection of a hypertonic solution into the blood stream will cause crenation, while a hypotonic solution will cause hemolysis. Why?
Concentration
Colligative properties
Vapor pressure lowering
Boiling point elevation
Freezing point depression
Osmosis and osmotic pressure

Key points:
 To relate the osmosis and osmotic pressure to the concentrations of solution
 To calculate osmotic pressure of electrolytes and nonelectrolytes
 To understand the importance of osmosis in medicine





 electrolyte 电解质  nonelectrolyte 非电解质  osmosis 渗透  osmotic pressure 渗透压  semipermeable membrane

半透膜 osmolarity 渗透浓度 isotonic 等渗的 hypotonic 低渗的 hypertonic 高渗的 hemolysis 溶血

（溶液的渗透与渗透压）
 Case 1 Isotonic solution
Surrounding sol’n at
9 g/L NaCl
Red blood cells normal .
 Case 2 Hypotonic solution
Surrounding sol’n less than 9g/L NaCl
Red blood cells rupture . Hemolysis
 Case 3 Hypertonic solution
Surrounding sol’n more than 9g/L NaCl
Red blood cells shrivel . Crenation

Problems
 What’s the Osmosis and Osmotic Pressure?
2.4.1 Osmosis （渗透）
 Experiment:
 On the left is a pure solvent , and on the right, a solution .
The two are separated by a semipermeable membrane . As a result, the water level rises on the right and drops on the left.

 Term:
 Semipermeable membrane -Certain membranes allow solvent molecules to pass through them but not solute molecules.
 Osmosis When a solution and its pure solvent are separated by a semi-permeable membrane, the pure solvent will diffuse through the membrane and dilute the solution.
This process is known as osmosis.

Problems
 Why ?
Solvent molecules can pass through the membrane in both directions, but the concentration of water is larger in the pure water, more water molecules strike the membrane per second on that side, and more water moves into the solution than leaves it.

Problems
 If a solution of lower C and a solution of higher C are separated by a semi-permeable membrane, will there be the osmosis? Why?
Concentrated solution
Semipermeable membrane
Dilute solution

Problems
 Condition ?

 a semipermeable membrane solutions of different C on either side of the membrane
Concentrated solution
Semipermeable membrane
Problems
 Direction ?
 from a solvent system to a solution system
 from the solution of lower C to the solution of higher C
Dilute solution

2.4.2 Osmotic pressure （渗透压）
 Term: The amount of pressure that must be exerted just to prevent net transport of solvent across a semipermeable membrane is the osmotic pressure.
 Symbol: π
 Unit:Pa (kPa)

Problems
 How to calculate the osmotic pressure ?
Van’t Hoff equation ： the gas constant
8.314 J • K -1 • mol -1
Osmotic pressure kPa
Π = c
B
RT the absolute temperature, K
Molarity of solutions mol• L -1

 Attention: c
B is the total molarity of all the dissociated solute species present.


Nonelectrolyte (非电解质): total molarity =c
B
Electrolyte ( 电解质 ) : total molarity = i c
B
1:1 NaCl→ Na + +Cl total m = 2 c
B
1:2 CaCl
2
→ Ca 2+ + 2Cl total m = 3 c
B i
 measured expected value colligativ e for a property nonelectro lyte

Nonelectrolyte ( 非电解质 )
Example1 When 2.00 g of sucrose ( 蔗糖， C
12
H
22
O
11
) is dissolved in 50.0 mL of water solution, what is the osmotic pressure at 37℃?
解： c (C H O )

12 22 11
 n
V
2.00g
342g mol

1 
0.0500L

B
 
1

0.117mol

L

1 
8.314J

K

1  mol

1 
310K

1kPa
1J

L

302kPa

Electrolyte ( 电解质 ):
Π ＝ i c
B
RT
Example 2 The 9.0 g ·L -1 salt (NaCl) solution is called physiological saline. What is the osmotic pressure at
37℃?
解：
Π ＝ i c
B
RT

2

9.0g

L

1 
8.314J
58.5g

K

1
 mol

1
 mol

1 
310K

1kPa
1J

7.9

10
2 kPa

Why ？ medicine physiological saline Less than 9 g/L more than 9 g/L
The red blood cells in different molarity solutions

2.4.3.1 Osmolarity( 渗透浓度 )


Term: osmotically active substances （渗透活性物质） ：
In body fluids, there are ions, small molecules, and large molecules. All these substances have an osmotic effect.
 osmolarity the total molarity of osmotically active substances c os def n os
/ V
  c i

c os def n os
/ V
Example 3 What is the osmolarity of (1) 50.0 g ·L -1 glucose (C
6
H
12
O
6
) solution and (2) 9.0 g ·L -1 salt (NaCl) solution ?
c os
( 葡萄糖 )

50.0 /180

1000

278

1 c ( NaC l) 2 os
 
9.00 / 58.5
1

1000

308


1

1

c os
  c i
Example 4 The 0.4 mol.L
-1 glucose (C
6
H
12
O
6
) solution
1L and 0.2 mol.L
-1 salt (NaCl) solution 1L are mixed with each other. What is the osmolarity of the final solution? c os
  c i
 c
葡萄糖
 c
Na

 c
Cl


0 .
2

0 .
1

0 .
1

0 .
4 mol

L

1

2.4.3.2 isotonic, hypertonic and hypotonic sulutions
Standard: blood plasma hypotonic isotonic hypertonic
280 mmol.
Ｌ -1
320 mmol.
Ｌ -1




Terms:
Isotonic: two solutions with the same
 separated by a semipermeable membrane.
Hypertonic: having a higher osmotic pressure
Hypotonic: a solution of lower
 than a isotonic solution.



Isotonic solution: 0.9%
(9g/L) NaCl
Red blood cells: osmolarity = 0.306mol/L
0.9% (9g/L) NaCl osmolarity = 2 × 9g/L
/58.5g/mol = 0.306mol/L
Red blood cells normal.

 Hypotonic solution:
0.5% (5g/L) NaCl
Red blood cells: osmolarity = 0.306mol/L
5g/L NaCl: osmolarity = 0.171mol/L
 Hemolysis ( 溶血 ): red blood cells placed in a hypotonic solution (relative to intracellular solution); there is a higher solute concentration in the cell; osmosis occurs and water moves into the cell. The cell bursts.

 Hypertonic solution:
1.5% (15g/L) NaCl
Red blood cells: osmolarity = 0.306mol/L
15g/L NaCl: osmolarity = 0.513mol/L
 Crenation （血栓） : red blood cells placed in hypertonic solution (relative to intracellular solution); there is a lower solute concentration in the cell than the surrounding tissue; osmosis occurs and water passes through the membrane out of the cell. The cell shrivels up.



Conclusion:
For intravenous feeding, it is necessary that the nutrient solution have exactly the osmotic pressure of blood plasma. If it does not, the blood cells may collapse or burst as a result of osmosis.
 To prevent crenation or hemolysis, solutions must be isotonic.
Standard: blood plasma
Range of Isotonic Solution: 280 ~ 320 mmol·L -1
Isotonic Solution: physiological saline solution
(9g/L NaCl), 50g/L glucose

Problems
 Examples of osmosis ?





Limp carrot placed in water becomes firm because water enters via osmosis.
Salty food causes retention of water and swelling of tissues (edema).
Water moves into plants through osmosis.
Salt added to meat or sugar to fruit prevents bacterial infection (a bacterium placed on the salt will lose water through osmosis and die)
Cucumber placed in NaCl solution loses water to shrivel up and become a pickle.

【 key points 】
1. Molarity- Molar Concentration ( 摩尔浓度，物质的量浓度 ) c
B def n
B
/ V
2. Osmosis and Osmotic Pressure （渗透与渗透压）
Π = i c
B
RT
3. isotonic, hypertonic and hypotonic sulutions
【 homework 】 p20 T2 ， T4 p39 T6 ， T9