Personal Introduction

Download Report

Transcript Personal Introduction

大学化学

印杰

(54742208,

[email protected]

课程中心：

http://202.120.43.111)

What is the purpose of this course?

• To understand the basic principles of chemistry • To understand how chemists think and work?

• • •

平时作业团组作业期末考试

考核方法

Chapter 1: Chemistry is a Science of Change

A water

molecule

is consisted of one oxygen ( 氧 ) atom and two hydrogen ( 氢 ) atoms.

A cup of water contains about 10 24 water molecules.

Chemistry is the study of how to form

atoms

( 原子 ) combine

materials

. ( 化学是研究原子组合成材料的科学 ) How many different types of atom: 114 so far.

They are listed (according to their structure and properties) in the

periodic table

( 元素周期表 ).

Period 2.4

Some atoms link together to form

molecules (

分子

)

and molecules are organized to form materials.

So Chemistry can also be defined as the study of matter and the transformations it can go.

是研究物质和物质转变的科学）（化学 Now millions of molecules have been found or synthesized ( 合成 ), and they form the complexity of the earth and the life.

The materials can be alloys, fertilizers, pharmaceuticals, polymers, computer chips, DNA, and more.

1.1 Chemistry is a central science useful to our lives

Most of the material items in any modern house are shaped by some human-devised chemical process.

• Chemistry and materials • Chemistry and health • Chemistry and energy

Chemistry and Materials Science

B-2战略轰炸机每架造价高达22亿美元的B-2战略轰炸机，是世上迄今最昂贵的飞机。机身采用翼身融合、无尾翼的飞翼构形，机翼前缘交接于机头处，机翼后缘呈锯齿形。机身机翼大量采用石墨-碳纤维复合材料、蜂窝状结构，表面有吸波涂层，发电机的喷口置于机翼上方。这种独特的外形设计和材料，能有效地躲避雷达的探测，达到良好的隐形效果.

Chemistry: A Science for the 21 st Century • Materials and Technology • Polymers, ceramics, liquid crystals • Room-temperature superconductors?

• Molecular computing?

• Food and Agriculture • Genetically modified crops • “Natural” pesticides • Specialized fertilizers 1.1

五颜六色的琥珀是由非常小的沙子有序自组装而成，由于排列顺序的变化，从而具有不同的光学性能

美丽的贝壳是由生物矿化材料有序排列，自组装得到

Chemistry and Biological Science and Health

H O H N H N N H N N N H H 3 C O DNA Double Helix H N H N H N H O N ÏÙàÑßÊ£¨ A£© N N H O H °û à×à¤£¨ C£© H ÄñàÑßÊ£¨ G£©

蚊子的眼睛具有防雾、减反和夜视的功能。它是由生物分子构成的纳米粒子自组装（有序排列）得到

蝴蝶的翅膀不会沾水，这是由于其翅膀是由光子晶体有序自组装形成了类似与瓦砌成的房顶结构，而且每一片瓦是由纳米纤维自组装而成，形成凹凸不平，具有沟槽结构，所以很容易将水排掉。

手性现象：化学分子式不足以表示分子结构，在生命体内分子的空间结构十分关键！ O O O OH H N O OH O O OH O O O O Taxol

Fig 14.4 originally isolated from the bark of the pacific yew tree, Taxol is a complex natural product useful in the treatment of various forms of cancer

Key

钥匙-锁模型

Lock

Drug molecule (morphine) Receptor site

T-shaped three dimensional structure found in all opioids morphine codeine heroine all drugs that act like morphine have the same basic three-dimensional shape as morphine

Chemistry and Energy

• • 我国产生世界

5%

的

GDP

，却消耗的世界约

20%

的化石燃料，不可持续。新的能源？ – 核能、风能、生物质能、太阳能、氢能

Hydrogen energy

：

Fuel cell

Overall Reaction: H 2 +O 2 =H 2 O Anode: H 2 -2e  2H + Cathode: O 2 +4e  2O 2  =1.23V

Chemistry and IC Industry

• 超大规模集成电路是信息科学领域的核心技术，但其制造工艺的 60% 以上是化学的应用：如 4Mb 的动态随机存取和存储器芯片制造工艺，有 164 个工艺步骤，其中有 118 个依据化学，包括化学合成、化学加工、化学处理等。

Key issues in chemistry:

Manipulating atoms and molecules to create materials to suit our needs.

(More types and larger quantity) Green chemical processes to reduce waste product and to protect the environment

A knowledge of chemistry gives us a handle on many of the questions and issues we face as a society.

Is genetically modified food safe?

Should fluoride be added to local water supply?

Why is it important to recycle?

What should be our primary energy resources in the future?

1.2 Science is a way to understanding the universe

(self-studying)

1.3 Physical quantity

unit ( 单位、量纲 ): what was measured.

Two major unit systems:

Customary System

of Units)

United States

( USCS, British System

Systeme International

(SI, metric system)

1.7

1.4 Physical Terms and Definations

Mass

( 质量 ) is the quantitative measure of how much matter a material object contains.

Weight

( 重量 ) is the gravitational forced exerted on an object by the nearest body.

Volume

( 体积 ) is the amount of space a material object occupies.

Energy

( 能量 ) is the capacity to do work.

Potential energy

( 势能 ) is the stored energy.

Kinetic energy

( 动能 ) is the energy of motion.

Temperature

( 温度 ) is a measure of how hot an object is, or is a measure of the average amount of energy is a substance.

Heat

( 热量 ) is the energy that flows from a higher-temperature object to a lower-temperature object.

Density

( 密度 ) is the ratio of mass to volume.

Chapter 2 Elements of Chemistry

Element

( 元素 ): any material consisting of one kind of atom.

Compound

( 化合物 ): A molecule consisting of atoms from different elements.

compound

is a substance composed of atoms of two or more elements chemically united in fixed proportions.

Compounds can only be separated into their pure components (elements) by

chemical

means.

Water (H 2 O) Glucose (C 6 H 12 O 6 ) Ammonia (NH 3 ) 1.4

2.1 Matter has physical and chemical properties

Physical properties

( 物理性质 ): properties that describe the look or feel of a substance, such as color, hardness ( 硬度 ), density, texture ( 质地 ), and phase ( 相态 ). When the conditions change, the physical properties of a substance may change, but that not mean a new substance has been created. This kind of property change is called

physical change

Chemical properties

( 化学性质 ): those that characterize the ability of a substance to react with other substances or to transform from one substance to another. Any change in a substance that involves a rearrangement of the way atoms are bonded is called a

chemical change .

In the language of

(

chemistry, this kind of change is called

chemical reaction

化学反应

)

. During the chemical reaction, substances are transformed to other new substances. Chemical reaction is the central point and the most important issue in chemistry. hydrogen burns in air to form water

How to determine whether a change is physical or chemical The physical change is usually the result of the change in condition and no new substances are formed. So restoring the original conditions restores the original physical properties.

2.2 Atoms are the fundamental components of elements

The great variety of substances results not from a great variety of atoms but from the many ways a few kinds of atoms can be combined.

To date, we know of about 115 different kinds of atoms. Of these, about 90 can be found in nature, and the remainder can be created in lab. So we also know about 115 elements. These elements can be listed in an organizing scheme called the periodic table.

Each element is designated by its

atomic symbol

, which comes from the letters of the element’s name.

Carbon: C, chlorine: Cl.

Some are from their latin name: Gold: Au (aurum), Lead: Pb (plumbum)

2.3 Elements can combine to form compounds

Sodium atoms and chlorine atoms bond to form sodium chloride.

Na + Cl → NaCl (

chemical formula,

化学式 ) Ammonia: NH 3

How to name compounds: according to the elements they contain A system for naming compounds (

systematic name

) was developed by International Union for Pure and Applied Chemistry (IUPAC).

系统命名法 Guideline 1: The name of the element farther to the left in the periodic table is followed by the name of the element farther to the right , with the suffix –ide added to the name of the latter.

Li 2 O: Lithium oxide CaF 2 : Calcium fluoride

Guideline 2: When teo or more non-metal compounds have different numbers of the same elements, prefixs are added to remove the ambiguity. Mono (one), di (two), tri (three) and tetra (four), and “mono”, sometimes, is omitted from the beginning of the first word of the name.

CO: carbon monoxide CO 2 : carbon dioxide Guideline 3:

Common names

being used for convenience.

Water, methane, ammonia. （俗名） are still

2.4 Most materials are mixture

mixture

( 混合物 ) is a combination of two or more substances in which each substance retains its properties.

Most materials we encounter are mixture:

Physical separation of mixtures Mixtures can be separated since they have different physical properties.

Phase difference: solid and liquid (

filtration

, 过滤 ). for making coffee and for purification of water.

distillation

Different boiling and melting points: making salt from seawater, obtain oxygen from air. (

distillation

, 蒸馏 )

2.5 Chemists classify matter as pure or impure

If a material is

pure

, it consists of only a single element or a single compound. It is extremely difficulty to obtain a pure material.

Water: water from river, tap water, bottled water, water used in IC industry Chemicals: chemically pure, analytically pure, pure enough for IC industry

1.4

2.6 Elements are organized in the periodic table by their properties

The discovery of periodic table has a long history.

period

( 周期 18 groups) ) is a horizontal row, a

group

( 族 ) a vertical column. (7 periods and Period: from left to right, conductivity decreases, (metal to nonmetal) the size of the atom decreases. This kind of repeating trend is called

periodicity

( 周期性 ).

Group: similar property.

Group 1: Alkali metals ( 碱金属 ) (from Arabic word for ashes) Group 2: Alkaline-earth metals ( 碱土金属 ) (named “earth” by alchemists because of their “fire-resistance”) Groups 3-12: transition metals ( 过渡金属 ) Group 16: Chalcogens ( 硫族 ) (“ore-forming” in Greek) Group 17: Halogens ( 卤素 ) (“salt-forming” in Greek) Group 18: Noble gases ( 惰性气体 ) Notes: In some of textbooks, the groups are divided into 8 main groups and 10 minor groups.