Properties of Solids · 固体的性质
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| molecular solids/məˈlekjʊlə ˈsɒlɪdz/ | 分子固体 | fèn zǐ gù tǐ |
| ionic solids/aɪˈɒnɪk ˈsɒlɪdz/ | 离子固体 | lí zi gù tǐ |
| metallic solids/məˈtælɪk ˈsɒlɪdz/ | 金属固体 | jīn shǔ gù tǐ |
| covalent-network solids/ˈkəʊvələnt ˈnetwɜːk ˈsɒlɪdz/ | 共价网络固体 | gòng jià wǎng luò gù tǐ |
Four kinds of solid
- Diamond scratches glass; candle wax melts in your hand.
- Both are solids, yet they could not be more different.
- The difference is what holds their particles together.
- Four bonding types give four families of solid.
四种固体
- 金刚石能划伤玻璃;蜡烛在你手中就融化。
- 两者都是固体,却再不同不过。
- 差别在于是什么把它们的粒子连在一起。
- 四种成键方式给出四大类固体。
Ionic and molecular solids
- Ionic solids 离子固体 are ions in a lattice: high-melting and brittle.
- Molecular solids 分子固体 are molecules held by weak forces: low-melting and soft.
- Ice and sugar are molecular; salt is ionic.
离子固体与分子固体
- 离子固体是晶格中的离子:高熔点、脆。
- 分子固体是被弱作用力维系的分子:低熔点、软。
- 冰和糖是分子固体;盐是离子固体。
Molecular solids tend to be soft with low melting points. · 分子固体通常质地柔软且熔点低。
They are held by weak intermolecular forces, easily broken. · 它们依靠微弱的分子间作用力结合，容易被破坏。
An ionic solid is hard but , shattering when a layer shifts. · 离子固体坚硬但，当层发生位移时会碎裂。
Shifting a layer aligns like charges, which repel and crack it. · 层位移导致同种电荷对齐，相互排斥从而开裂。
Network and metallic solids
- Covalent-network solids 共价网络固体 are one giant bonded lattice: very hard, very high-melting (diamond).
- Metallic solids 金属固体 are cations in an electron sea: they conduct and bend.
- Each type's properties follow directly from its bonding.
网络固体与金属固体
- 共价网络固体是一整块巨大的成键晶格:很硬、熔点很高(金刚石)。
- 金属固体是电子海中的阳离子:能导电、能弯折。
- 每一类的性质都直接由它的成键方式决定。
Diamond is very hard with a very high melting point. It is a... · 金刚石非常坚硬且熔点极高。它是...
One giant lattice of strong covalent bonds makes it hard and high-melting. · 由强共价键构成的巨大晶格使其坚硬且高熔点。
Match each solid to its type. · 将每种固体与其类型匹配。
Salt = ionic, diamond = covalent network, copper = metallic. · 盐=离子型，金刚石=共价网络型，铜=金属型。
Reading properties from bonding
- Strong, extended bonding gives a high melting point and hardness.
- Free-moving charges (ions when molten, electrons in metals) give conductivity.
- Weak forces give soft, low-melting molecular solids.
从成键读出性质
- 强而延展的成键给出高熔点和硬度。
- 可自由移动的电荷(熔融时的离子、金属中的电子)给出导电性。
- 弱作用力给出软的、低熔点的分子固体。
What kind of solid? · 这是哪种固体？
Match each solid's properties to its structure type. · 将每种固体的性质与其结构类型匹配。
Which type of solid conducts electricity in the solid state? · 哪种类型的固体在固态下能导电？
Only metals have mobile electrons in the solid; ionic needs melting first. · 只有金属在固态下拥有自由移动的电子；离子化合物需先熔化。
Why does diamond melt far hotter than dry ice (solid $\text{CO}_2$)?
- Diamond is a covalent network, so melting must break strong bonds.
- Dry ice is molecular, so melting only breaks weak forces between molecules.
为什么金刚石的熔点远高于干冰(固态 $\text{CO}_2$)?
- 金刚石是共价网络,所以熔化必须断开强键。
- 干冰是分子固体,所以熔化只断开分子之间的弱作用力。
Melting dry ice (solid $\text{CO}_2$) breaks... · 融化干冰（固体$\text{CO}_2$）破坏了...
It is a molecular solid, so only the weak intermolecular forces break. · 它是一种分子固体，因此只有微弱的分子间作用力被破坏。
Do not confuse the strong bonds inside a molecule with the weak forces between molecules -- melting a molecular solid breaks only the weak forces. Only metals conduct as solids; ionic solids conduct just when molten or dissolved; covalent networks and molecular solids usually do not conduct at all.
不要把分子内部的强键与分子之间的弱作用力混淆——熔化分子固体只断开弱作用力。只有金属在固态导电;离子固体只在熔融或溶解时导电;共价网络和分子固体通常完全不导电。
Four solids follow from four bondings: ionic solids (lattice of ions, brittle), molecular solids (weak forces, soft, low-melting), covalent-network solids (giant lattice, very hard), and metallic solids (electron sea, conducting). Strong extended bonding means high melting; free charges mean conduction.
四种固体源自四种成键:离子固体(离子晶格,脆)、分子固体(弱作用力,软,低熔点)、共价网络固体(巨大晶格,很硬)、金属固体(电子海,导电)。强而延展的成键意味着高熔点;自由电荷意味着导电。