英國語文第五冊(雙語):蠟燭的化學(xué)組成(3)

00:00

00:00

MP3下載

https://online2.tingclass.net/lesson/shi0529/10000/10356/ygyw5_35.mp3

https://image.tingclass.net/statics/js/2012

"But,"proceeded Harry, "there is more in the candle-flame than the gas that comes out of the candle. You know a candle won't burn without air. There must be always air around the gas, and touching it, as it were, to make it burn. If a candle hasn't got enough of air it goes out, or burns badly, so that some of the vapour inside of the flame comes out through it in the form of smoke; and this is the reason of a candle smoking. So now you know why a great clumsy dip smokes more than a neat wax candle: it is because the thick wick of the dip makes too much fuel in proportion to the air that can get to it.

“但是,”哈利繼續(xù)說,“相對與蠟燭產(chǎn)生的氣體，這里有更多的是在燭焰里的。你知道蠟燭沒有空氣不會燃燒。必須時(shí)常有空氣在氣體周圍,接觸它,讓它燃燒。如果蠟燭沒有足夠的空氣它會熄滅,或燒的很糟糕,以致一些火焰內(nèi)部的蒸汽通過煙霧的形式出來,這是蠟燭出煙的原因。所以現(xiàn)在你知道為什么一個浸潤的厚芯出的煙超過一個干凈整潔的蠟燭:那是因?yàn)榻櫟暮裥臼谷剂显诳傻玫降目諝庵姓继蟮谋壤?/p>

"What should you say now," continued Harry, "if I were to tell you that the smoke that comes out of a candle is the very thing that makes a candle burn with a bright light? Yes; a candle shines by consuming its own smoke. The smoke of a candle is a cloud of small dust; and the little grains of dust are bits of charcoal, or carbon, as chemists call it. They are burned the moment they are made; and the place they are made in is the case of flame itself, where the strongest heat is. The great heat separates them from the gas which comes from the melted wax; and as soon as they touch the air on the outside of the thin case of flame they burn."

“現(xiàn)在你該說些什么,”哈利繼續(xù)說,“如果我告訴你,蠟燭里出來的煙是讓蠟燭燃燒著明亮燈光的重要東西?是的,蠟燭明亮是通過利用自己產(chǎn)生的煙。蠟燭的煙是一堆小的粉末塵埃組成,小顆粒的粉塵是少量木炭類,或碳，化學(xué)家這樣叫它。它們產(chǎn)生的時(shí)候就燃燒了,而且他們產(chǎn)生的地方是在火焰本身燃燒的情況下,熱量最強(qiáng)的地方。最大的熱力將它們和那些從融化的蠟中來的氣體分離，一旦接觸外面稀薄的空氣，他們會燃燒?！?/p>

"Can you tell me how it is that the little bits of carbon cause the brightness of the flame?" asked Mr. Wilkinson.

“你能告訴我為何小分子的碳會調(diào)節(jié)火焰的亮度嗎?”威爾金森先生問。

"Because they are pieces of solid matter," answered Harry. "To make a flame shine, there must always be some solid, or at least dense, matter in it."

“因?yàn)樗麄兪枪腆w物質(zhì),”哈利回答。“讓火焰閃光,必須時(shí)常有立體的,或者至少密集的,物質(zhì)在里面?！?/p>

"Very good," said Mr. Bagges; "solid stuff necessary to brightness!"

Bagges先生說,“很好,立體的東西是亮度的必需!”

"Some gases and other things," resumed Harry, "that burn with a flame you can hardly see, burn splendidly when something solid is put into them. Hydrogen gas if blown through a pipe, burns with very little light; but if the flame is blown upon a piece of quick-lime, it gets so bright as to be quite dazzling. If you now send some oxygen on to the flame, the flame gets no brighter, but the lime shines like a little sun. Make the smoke of oil of turpentine pass through the same oxygen, and it gives the flame a beautiful brightness directly. Well, carbon, or charcoal, is what causes the brightness of all lamps, and candles, and other common lights; so, of course, there is carbon in what they are all made of."

“氣體和其他一些東西“哈利繼續(xù),“火焰燃燒你幾乎看不到,當(dāng)某些固體物質(zhì)加入里面時(shí)燃燒會變得耀眼。氫氣體如果吹入管道,燃燒的光亮很小;但是,如果火焰吹在一塊生石灰,它會變得明亮,很刺眼。如果你現(xiàn)在輸一些氧氣到火焰中,火焰不會變得更亮,但石灰燃燒得光如同小陽光。讓松節(jié)油的煙霧通過相同的氧氣,它確實(shí)會給出一簇漂亮明亮的火焰。好，碳分子,或木炭,是調(diào)控所有燈的亮度,還有蠟燭,和其他常見燈的原因;所以,當(dāng)然,這些所有的都會產(chǎn)生碳?！?/p>

"So carbon is smoke, eh? and light is owing to your carbon. Giving light out of smoke, eh? as they say in the classics," observed Mr. Bagges.

“所以碳是煙,是嗎?并且亮度是由你的碳調(diào)控。發(fā)光是用煙,是嗎?正如他們在經(jīng)典里所說的,”Bagges先生評述說。