Topic: Chemistry - English Discussions

化学话题 - 英语讨论



  • atom: the smallest unit of an element
  • Molecule 分子
  • particle 粒子
  • solution 溶液
  • distillation 蒸馏(盐水蒸馏,分离水和盐)Distillation is the process of separating the components of a liquid mixture through selective evaporation and condensation. The basis of separation is the difference in the vapor pressures (volatilities) of the respective components.
  • solubility 溶解型
  • dissolve 溶解
  • blend 混合
  • compound 合成
  • crystal 结晶
  • compound: a chemical combination of two or more elements
  • element: a pure substance that cannot be broken down any further
  • Propane(丙烷, C_3H_8): is a fossil fuel. It’s stored in pressure tanks so it can be transported as a liquid. Propane is used for heating barbeque grills, campers, and other spaces where portable fuel is needed.
  • acidification 酸化;成酸性;使……发酸
  • acid/alkaline 酸碱
  • oxidation 氧化
  • infiltrated our environment 渗透到我们的环境中
  • doxide 二氧化物
  • silicate 硅酸盐


  • glass bottle 小瓶子(上下一样大)
  • funnel 漏斗,烟囱(上大下小,底部孔)
  • flask 烧瓶 长颈瓶(下大,上小,储存)
  • side-arm flask
  • beaker 烧杯
  • measuring cylinder 量杯
  • stand 架子
  • clamp 夹子
  • stopper 塞子
  • test tube 试管
  • tub 浴缸
  • rack 架子
  • petri dish 培养皿
  • glass rod 玻璃杆
  • pipette 滴定管
  • pestle 杵
  • mortar 灰浆
  • forceps 镊子(cep-拿,fore-前)
  • spatula 抹刀
  • dilute sulfuric acid 稀释的硫酸
  • copper salfate solution 硫酸铜溶液
  • agent 试剂
  • zinc 锌
  • tin 锡
  • granules 颗粒(granule 的复数);颗粒剂
  • oscillating 震荡
  • photon 光子
  • EM radiation:electromagnetic (EM) radiation
  • photodissociation 光离解(UV + H2O = H2↗ + O↗)

Unit 1: Atoms, elements, and the periodic table

Atom 原子

Atoms make up everything in our world.

  • Atom 原子(a-步,tom切,不可再分):
  • Nucleus: composed of protons and neutrons
  • Proton 质子(正电), 1u
  • Neutron 中子(不带电,和质子质量一样),has no charge, 1u
  • Electron: outside the nucleus, electron cloud, 电子(带负电,质量很小,可忽略不计)
  • isotopes 同位素(质子数目相同,种子数不同。化学性质相同,重量不一样)
  • noble gas 惰性气体(不活跃,不和其他反应。Helium氦(He), Neon氖(Ne), Argon氩(Ar), Krypton氪(Kr), Xenon氡(Xe))通电以后颜色不同
  • subatomic articles
  • charge and mass: 充电和质量
  • unified atomic mass unit(u)
  • physical property: a property that describes a matter by itself

Elements and atomic number

There are many different types of atoms called elements, each with a unique set of physical and chemical properties.

A particular element is idenfied by the number of protons in its atoms. The number of protons in the nucleus of an atom is its atmoic number, represented by the symbol Z.

All of the known elements are organized according to their atomic numbers in the periodic table(元素周期表).


mass = # of protons + # of neutrons


燃素说 (Phlogiston theory)

phlogiston, in early chemical theory, hypothetical principle of fire, of which every combustible substance was in part composed. In this view, the phenomena of burning, now called oxidation, was caused by the liberation of phlogiston, with the dephlogisticated substance left as an ash or residue.


燃素说,是一个已被取代的化学理论,起源于17世纪。这个理论假设,任何物质在燃烧时,都会释放出一种名叫燃素的成分。 这个学说于18世纪被法国化学家安托万-洛朗·德·拉瓦节推翻。


  • nucleus 核
  • proton 质子(有重量,带正电)
  • neutron 中子(有重量,不带电)
  • electron 电子(带负电)
  • isotope 同位素(同一种元素的所有同位素都具有相同的质子数目,但中子数目不同,故质量数不同。)
  • hydrogen 氢
  • helium 氦
  • lead n. 铅
  • ammonia 氨
  • alkali 碱: slippery, taste bitter, PH > 7, react with acids to form salts
  • ceramics 陶瓷
  • red litmus paper 红色石蕊试纸
  • ionic compound 离子化合物
  • hydroxides
  • carbanions
  • catalyst n. 催化剂
  • combustible 易燃的
  • biochemical 生物化学的
  • ductile 柔软的;易教导的;易延展的
  • evaporation 蒸发
  • iron 铁
  • potassium 钾
  • a colorless and odorless fluid 无色无味的液体
  • hydroxide 氢氧化物
  • periodic table 元素周期表
  • diluted 经稀释的,淡的
  • Nitric acid 硝酸。是一种具有强氧化性、腐蚀性的强酸,属于一元无机强酸,是六大无机强酸之一,也是一种重要的化工原料,化学式为HNO₃,其水溶液俗称硝镪水或氨氮水。
  • acidity 酸度,酸性
  • phosphorus 磷
  • magnesium 镁
  • halogens 卤素
  • noble gases 惰性气体
  • metalloids 非金属材料
  • nonmetals 非金属
  • metals 金属
  • transition metal 过渡金属
  • atomic number 原子数
  • average atomic mass 平均原子质量
  • Metalloids 类金属
  • Atomic Radii Trends
  • valance electrons 外层电子
  • atomic radii trends 原子半径趋势
  • high energy level 高能量级别(越外层)越高级
  • period 一行(periodic table)
  • group: column in the periodic table
  • nitride 氮化物
  • homogeneous mixture 均匀混合物
  • heterogeneous mixture 异质混合物
  • A molecule is a group of two or more atoms covalently bonded together.
  • Molecules(分子) are held together by covalent bonds.是共价键形成的,盐不属于分子。
  • Ionic bonds 离子键(salt)
  • Covalent bond 共价键(Molecular oxygen,Water)
  • Covalent network solids(silica,沙子,二氧化硅)
  • compound(化合物):A compound is a chemical substance composed of two or more different elements. Compounds can be covalently or ionically bonded.
  • Chemicals(化学品):A chemical (or chemical substance) is any substance with a definite composition. All of the preceding categories—molecules, salts, and compounds—are chemicals. In some situations, you may see the word “chemical” used to refer exclusively to substances that are harmful or made in a laboratory. From a chemistry perspective though, even pure water is a chemical.

Ion 离子(带电)

  • Ion: different number of protons and electrons.
  • anion: 负离子,带负电
  • cation: 阳离子,带正电

The electromagnetic spectrum

Ultraviolet 紫外线

Radio(building) -> microwave(butterflies) -> infrared(needle point) -> visible(protozoans) -> ultraviolet(molecules) -> X-ray(Atoms) -> Gamma ray(Atomic Nuclei)

But, EM radiation travels at a slower speed in matter, such as water or glass.

Electromagnetic radiation consists of oscillating electric and magnetic fields. It can be modeled both as waves and as particles called photons. All EM radiation, from radio to gamma, travels at speed c in a vacuum. The higher the frequency of EM radiation, the higher the energy of the photons.

Human eyes can only see the visible light portion of the spectrum directly. However, we can use various detectors to make the other regions of the EM spectrum visible to us.

Finally, notice on the bottom of the EM spectrum diagram that photon energy increases as frequency increases.

Unit 2: Chemical Bonding(化学键)

Three Types of Bonds(Atomic Bonding)

  • Ionic bonding: a bond formed between a metal atom and a nonmetal atom(metal-nonmetal, salt)
  • Covalent bonding: a bond formed between two nonmetal atoms(nonmetal-nonmetal, oxygen, carbon dioxide)
  • Metallic bonding: a sea of eletrons shared within metal atoms(metal-metal, iron)

meatls: conduct electricity, malleable(有延展性, you can bend them without breaking), solid at room temperature

nonmetals: gasses(room temperature), not conduct electricity, nobel gasses



  • potassium 钾
  • sodium 钠
  • calcium 钙
  • magnesium 镁
  • aluminium 铝(电解铝)
  • carbon
  • zinc
  • iron
  • copper
  • ore 矿石
  • molten slag 熔化的矿渣

酸根 Solubility patterns

  • nitrate 硝酸根 NO3
  • chloride 盐酸根 Cl
  • sulfate 硫酸根
  • carbonate 碳酸根 CO3
  • hydroxide 氢氧根 OH


  • ammonium 铵
  • potassium 钾
  • sodium 钠
  • barium 钡
  • calcium 钙
  • magnesium 镁
  • aluminium 铝(电解铝)
  • zinc 锌
  • iron 铁
  • lead 铅,领导
  • copper 铜
  • brass 黄铜
  • bronze 青铜(copper + tin 增加硬度)
  • silver 银


  • carbon
  • hydrogen
  • nitrogen
  • sulfur


  • Barium sulfate(baryte, yellow) 硫酸钡
  • Polypropylene(PP) 聚丙烯 plastic(PP is composed of long chains of carbon and hydrogen atoms bonded together.)
  • Sodium bicarbonate(碳酸氢钠) is commonly known as baking soda. It’s added to many batters because it reacts during baking to produce gas bubbles, creating a light texture in the finished product.
  • Calcium fluoride 氟化钙,萤石:Calcium fluoride is an ionic compound. In nature, it occurs as a mineral called fluorite. Pure fluorite is colorless, but different impurities(杂质) inside the mineral produce a variety of colors.
  • Hydroxyapatite: It is the primary component of bone mineral and tooth enamel. 它是骨矿物质和牙釉质的主要成分。
  • potassium bromide 溴化钾
  • hydrocarbon 碳氢化合物
  • gasoline 汽油
  • petroleum 石油
  • oxygen 氧气
  • bronze 青铜(harder than copper, tin+copper)
  • brass 黄铜
  • limestone 石灰石,碳酸钙
  • plastic 塑料
  • Barium carbonate 碳酸钡;As a mineral, barium carbonate is called witherite.
  • Aspirin is a medicine used to treat pain, fever, and other conditions.


  • silicon 硅
  • copper 铜
  • lead(Pb) 铅,领导
  • mercury 水银
  • nickle 镊
  • sodium 钠
  • calcium 钙
  • Barium 钡
  • nitrogen 氮
  • phosphorus 磷(P)


  • sulfate 硫酸盐(SO_4)
  • Cyanide 氰化物


  • erode-erosion 腐蚀(风,地貌)
  • rot 腐烂
  • decay 衰退
  • decomposition 分解
  • Rust 生锈

PH and indicators 酸碱值

  • The ph scale
  • alkaline 草木灰(中东),碱性
  • base 碱;基础

Ionization is the process of removing an electron from a neutral atom (or compound). The energy required to remove an electron is the ionization energy. The ionization energy differs for each atom. There are trends that match the structure of the periodic table. Across a period, ionization energy tends to increase. Down a group, the ionization energy tends to decrease. Created by Sal Khan.

The number of valence electrons determines most of an atom’s chemical behaviors. So, it’s important to be able to identify how many valence electrons atoms of different elements have.

Absorption spectra of start(元素检测)

  • Continuous spectrum: A continuous spectrum shows all the frequencies or wavelengths of visible light.
  • Absorption line spectrum: produced when electrons absorb energy and transition from lower to higher energy levels
  • Emission line spectrum: An emission line spectrum is produced when electrons emit energy and transition from higher to lower energy levels.

Each element has its own unique absorption spectrum. By comparing the absorption spectra of stars with the absorption spectra of known elements, the elemental composition of the star can be determined.

Unit 3: Chemical Reactions

Physical and chemical changes

  • physical change: water -> ice
  • chemical change: change in composition

Endothermic and exothermic reactions 吸热和放热反应


Development of the Periodic Table 元素周期表的演进

  • interplay: interaction
  • abundance: plenty
  • analogous to: similar to 相似,模拟

The periodic table introduced by Meyer and Mendeleyev was the forerunner of the modern table of elements.

Mendeleyev and Meyer organized the known elements into a chart that revealed periodic recurrences of chemical and physical properties. Mendeleyev’s successful prediction of the properties of then- unknown elements lent support to the acceptance of the periodic law. In the 1890’s, Ramsay and Lord Rayleigh isolated argon and proposed the existence of a new series of elements.


Mixtures and Solutions

  • blend 混合
  • alloy
  • stir 搅拌
  • physical changes and chemical changes
  • solution 溶液
  • mixture 混合物
  • unite 团结
  • retain
  • remain
  • alloy 合金
  • brass(copper + zinc) 黄铜(铜+锌)
  • solvent 溶剂
  • solute 溶质

A solution is a mixture in which all of the substances are blended completely. There many types of solutions. Sugar water is one example of a solution. In this case, the water is called the solvent while the sugar is called the solute.

Copper and allo合金 and metals金属

If these little shellfish adhere to the hull of a ship, it produces drag, slowing the vessel down.


Copper’s also a key material used in solar heating units and in water desalination plants, which will play increasingly important roles in society.


Two Kinds of Mixtures

Now, there are two main kinds of mixtures: homogeneous and heterogeneous.


  • homogeneous(solution,溶液): salt and water(no boundary), can be separated by distillation(蒸馏)

  • heterogeneous: oil and water, smoke,dirty water(have boundary, see components), can be separated by filtration.(过滤, filter paper)

  • taste

  • color

A solution of salt water, for example, will have a different freezing point depending on how much salt is dissolved in the water.