Presentation on theme: "大学化学 印杰 (54742208, 课程中心："— Presentation transcript:
大学化学 印杰 ( , 课程中心：
What is the purpose of this course? To understand the basic principles of chemistry To understand how chemists think and work?
考核方法 平时作业 团组作业 期末考试
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 water molecules.
Chemistry is the study of how atoms ( 原子 ) combine to form 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 Group Alkali Metal Noble Gas Halogen Alkali Earth Metal 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. （化学 是研究物质和物质转变的科学） 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: 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
Chemistry and Biological Science and Health DNA Double Helix
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 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！
钥匙 - 锁模型 Drug molecule (morphine) Receptor site Lock Key
all drugs that act like morphine have the same basic three-dimensional shape as morphine T-shaped three dimensional structure found in all opioids morphine codeineheroine
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。
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 Key issues in chemistry:
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: United States Customary System ( USCS, British System of Units) Systeme International (SI, metric system)
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.
A 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 （俗名） are still being used for convenience. Water, methane, ammonia.
2.4 Most materials are mixture A 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
2.6 Elements are organized in the periodic table by their properties The discovery of periodic table has a long history. A period ( 周期 ) is a horizontal row, a group ( 族 ) a vertical column. (7 periods and 18 groups) 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.
Period Group Alkali Metal Noble Gas Halogen Alkali Earth Metal 2.4
In the sixth and seventh periods, there are two subsets of elements named inner transition metal. Elements with numbers are named lanthanides ( 镧系 ). These elements have very useful application in microelectronic industry. Those with numbers are called actinides ( 锕系 ). They are usually used in nuclear power industry and the purification is very difficulty.