Hydrogen bonding · 氢键
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| hydrogen bonding/ˈhaɪdrədʒn ˈbɒndɪŋ/ | 氢键 | qīng jiàn |
| electronegative/ɪˈlektrəʊŋɡətɪv/ | 电负性 | diàn fù xìng |
| lone pair/ləʊn peə/ | 孤对电子 | gū duì diàn zi |
| surface tension/ˈsɜːfɪs ˈtenʃn/ | 表面张力 | biǎo miàn zhāng lì |
The strongest weak force
- Hydrogen bonding 氢键 is a strong, special case of permanent dipole forces.
- It needs hydrogen bonded to a very electronegative 电负性 atom.
- It explains the strange behaviour of water.
最强的弱力
- 氢键(hydrogen bonding) 是永久偶极力的一个强的、特殊的情况。
- 它需要氢与一个 非常电负性 的原子成键。
- 它解释了水的奇怪行为。
Hydrogen bonding is the strongest of the intermolecular forces covered here. · 氢键是这里讲到的分子间作用力中最强的。
Hydrogen bonding is a particularly strong type of permanent dipole force. · 氢键是一种特别强的永久偶极力。
Hydrogen bonding occurs when H is bonded to N, O or F. · 氢键发生在 H 与 N、O 或 F 成键时。
It explains water's high boiling point. · 它解释了水的高沸点。
When it forms
- It forms when hydrogen is bonded to nitrogen, oxygen or fluorine (N, O, F).
- That $\delta+$ hydrogen is attracted to a lone pair 孤对电子 on an N, O or F atom nearby.
- Look for N–H and O–H groups (as in ammonia and water).
Hydrogen bonding between water molecules: an H is attracted to a lone pair on a neighbour's O
它何时形成
- 当氢与 氮、氧或氟(N、O、F)成键时形成。
- 那个 $\delta+$ 氢被附近一个 N、O 或 F 原子上的 孤对 吸引。
- 寻找 N–H 和 O–H 基团(如氨和水中)。
水分子之间的氢键:一个 H 被邻居 O 上的一个孤对吸引
Why hydrogen bonds make water special · 为什么氢键让水如此特别
Step through it. One weak-but-strong force — the hydrogen bond — explains water's high boiling point, why ice floats, and why it dissolves so much. · 一步步走过去。一种弱中带强的作用力——氢键——解释了水的高沸点、冰为什么浮起来、以及它为什么能溶解那么多东西。
Hydrogen bonding forms when hydrogen is bonded to: · 氢键在氢与以下原子成键时形成:
H must be bonded to a very electronegative atom (N, O or F) and be attracted to a lone pair on N/O/F nearby. · H 必须与一个非常电负性的原子(N、O 或 F)成键,并被附近 N/O/F 上的一个孤对吸引。
Why water is special
- High melting and boiling points — many hydrogen bonds must be broken.
- High surface tension 表面张力.
- Ice is less dense than water — hydrogen bonds hold an open structure, so ice floats.
为什么水很特别
- 高熔点和沸点——许多氢键必须被断开。
- 高表面张力。
- 冰比水密度小——氢键保持一个开放的结构,所以冰 浮起来。
Match each special property of water to the reason for it. · 把水的每个特殊性质与它的原因配对。
Every "special" property of water comes back to its many hydrogen bonds. · 水的每个"特殊"性质都回到它的许多氢键上。
Water has a high boiling point because: · 水有高沸点,因为:
The extra energy needed to break the many hydrogen bonds raises water's boiling point. · 断开许多氢键所需的额外能量升高了水的沸点。
Ice floats on water because: · 冰浮在水上,因为:
In ice the hydrogen bonds space the molecules out, making it less dense than liquid water, so it floats. · 在冰中,氢键把分子隔开,使它比液态水密度更小,所以它浮起来。
The power of hydrogen bonding
Worked example. Water boils at 100 °C while H₂S (no hydrogen bonding) boils at −60 °C — even though H₂S is heavier. Hydrogen bonds make the difference.
氢键的威力
例题。 水在 100 °C 沸腾,而 H₂S(没有氢键)在 −60 °C 沸腾——尽管 H₂S 更重。氢键造成了这个差别。
You've got it
- hydrogen bonding needs H bonded to N, O or F, attracted to a lone pair on N/O/F
- look for N–H and O–H groups
- it gives water a high boiling point, high surface tension, and makes ice float (open structure)
你掌握了
- 氢键 需要 H 与 N、O 或 F 成键,被 N/O/F 上的一个孤对吸引
- 寻找 N–H 和 O–H 基团
- 它给水 高沸点、高表面张力,并使 冰浮起来(开放结构)