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Many ionic compounds do not just exist in a laboratory or in your chemistry homework.
許多離子化合物並不僅僅存在於實驗室或化學作業中。
Sodium chloride is regular table salt.
氯化鈉是普通食鹽。
Sodium fluoride is added to some toothpastes to help strengthen tooth enamel.
有些牙膏中添加了氟化鈉,以幫助強化牙齒琺琅質。
Ammonium nitrate can be used to fertilize plants.
硝酸銨可用於植物施肥。
Although their real-life applications are very different, they share a few key properties.
雖然它們在現實生活中的應用大相徑庭,但卻有一些共同的關鍵特性。
In this lesson, we will learn about the properties of ionic compounds.
本課我們將學習離子化合物的性質。
These ionic compounds have very high melting points and are brittle because of their 3D giant ionic lattice structure.
這些離子化合物具有很高的熔點,並且由於其三維巨型離子晶格結構而比較脆。
The strong electrostatic attractions holding the 3D lattice structure in place mean that a lot of energy is required to overcome these attractions.
固定三維晶格結構的強大靜電吸引力意味著需要大量能量才能克服這些吸引力。
When we apply a force, it breaks the regular repeating pattern of oppositely charged ions, causing ions with like charges to come close to one another.
當我們施加一個力時,它就會打破帶相反電荷的離子的規則重複模式,使帶相同電荷的離子相互靠近。
The ensuing repulsion breaks the lattice structure.
隨之而來的斥力會破壞晶格結構。
Sodium chloride, sodium fluoride, and ammonium nitrate can all dissolve in water, as we know.
我們知道,氯化鈉、氟化鈉和硝酸銨都能溶於水。
Or else, we wouldn't be able to flavor our soups, brush our teeth, or fertilize our plants.
否則,我們就無法給湯調味、刷牙或給植物施肥。
Most ionic compounds are soluble in water.
大多數離子化合物都能溶於水。
In water, an ionic compound can dissociate into its ions.
在水中,離子化合物可以解離成離子。
So when we dissolve sodium chloride, it will dissociate into sodium and chloride ions.
是以,當我們溶解氯化鈉時,它會離解成鈉離子和氯離子。
These ions become stabilized in water due to the polar nature of water.
由於水的極性,這些離子在水中變得穩定。
As you can see, the sodium ions are stabilized by the negative dipole of water, and the chloride ions are stabilized by the positive dipoles of water.
正如您所看到的,鈉離子被水的負偶極子所穩定,而氯離子則被水的正偶極子所穩定。
This solvation stabilizes the free-floating ions.
這種溶解作用穩定了自由漂浮的離子。
An ionic compound dissolved in water can conduct electricity.
溶於水的離子化合物可以導電。
This is another key property of ionic compounds.
這是離子化合物的另一個關鍵特性。
This is made possible due to the presence of free-floating ions.
這得益於自由浮動離子的存在。
We can dissolve copper 2-sulfate in water in a beaker.
我們可以在燒杯中將 2-硫酸銅溶於水。
Add a few drops of sulfuric acid.
加入幾滴硫酸。
Place a strip of copper and a strip of zinc into the solution.
將一條銅帶和一條鋅帶放入溶液中。
These will act as electrodes.
這些將充當電極。
Using two alligator clips, connect one strip to one end of the mini light bulb, and another strip to the other end to complete the circuit.
用兩個鱷魚夾將一條連接到迷你燈泡的一端,再將另一條連接到另一端,完成電路。
You will see that the light bulb lights up.
你會看到燈泡亮起。
Hence, the solution conducts electricity.
是以,溶液會導電。
Following on the same idea, molten ionic compounds can also conduct electricity.
按照同樣的思路,熔融離子化合物也能導電。
The lattice structure is broken at high temperatures, and so the ions become free-floating.
在高溫下,晶格結構被破壞,是以離子變得自由漂浮。
In summary, ionic compounds have high melting points, are brittle, and can conduct electricity when dissolved in water or molten due to the presence of free-floating ions.
總之,離子化合物熔點高、脆性大,由於存在自由浮動的離子,溶於水或熔融時可以導電。
For more information, visit www.nasa.gov
欲瞭解更多資訊,請訪問 www.nasa.gov