時(shí)差N小時(shí):火是什么 What is the fire
這是我們最重要的工具之一，在很多古哲學(xué)和古宗教中占有很顯著的地位。
The ancient Greeks believed that fire–along with earth, water, and air–was one of the fouressential elements that made up the world.
古希臘認(rèn)為，火，土，水和氣是組成這個(gè)世界的四個(gè)基本要素。
We now know that the world's a lot more complicated, with over a hundred elements of matterwhich can be combined in a tremendous variety of ways.
現(xiàn)在，我們知道世界的構(gòu)成其實(shí)是更加復(fù)雜的，由上百種物質(zhì)組成，而同時(shí)這些物質(zhì)又可以以無(wú)數(shù)種不同的方式結(jié)合。
This might leave you wondering where fire fits in. What exactly is fire?
那這就讓你感到奇怪了，火是從哪里來(lái)的，具體是什么東西呢?
Watching a flame dance through the air, you might conclude that fire's a gas, like oxygen orcarbon dioxide.
看到空氣中的跳動(dòng)的火苗，你可能會(huì)覺得火是一種氣體，像氧氣，二氧化碳那類的。
It's not. Fire can burn fuel that's a gas, or a liquid, or even a solid–as in the case of glowingcharcoal.
其實(shí)不是?；鹂梢允箽怏w，液體甚至是固體燃料燃燒-比如燃燒的木炭。
But the fire itself isn't any of these things.
但是火本身并不是這些東西的任何一個(gè)。
In fact, fire isn't any thing at all.
實(shí)際上，火沒(méi)有自身的形態(tài)。
It's not its own type of matter; it's something that matter can do.
它不是物質(zhì)，但卻起到一些物質(zhì)的作用。
Fire is a chemical reaction.
火是一種化學(xué)反應(yīng)。
A fire needs oxygen and some kind of fuel.
火是需要氧氣和某種燃料共同作用的。
This fuel–whether it's candle wax, wood, or gasoline–usually contains big molecules thathave carbon atoms inside them.
這些燃料不管是石碏、木頭還是天然氣通常都會(huì)含有大量的碳分子。
You can think of these molecules as little containers of energy.
你可以將這些分子想象成小小的儲(chǔ)能體。
When they're allowed to combine with oxygen, this energy is released as heat and light.
當(dāng)它們與氧氣結(jié)合時(shí)，這些能量就會(huì)作為光和熱釋放。
Fire is a rapid chemical reaction known as oxidation.
火是一種快速的氧化化學(xué)反應(yīng)。
Inside a fire, oxygen molecules break bigger molecules apart into carbon dioxide and watervapor.
在火中，氧分子將更大的分子氧化成二氧化碳和水蒸汽，火中的所有光和熱都來(lái)自于含碳的大分子同氧氣的結(jié)合。
All the heat and light of a fire comes from big, carbon-based molecules combining withoxygen.
火所有的熱和光來(lái)源于碳分子和氧氣結(jié)合的反應(yīng)。
So what is fire? It's not the fuel or the oxygen or the heat or the light.
那么到底什么是火?它不是燃料，不是氧氣，也不是光和熱。
Fire is what happens between all these things. It's a chemical reaction.
火就是它們之間所產(chǎn)生的一種化學(xué)反應(yīng)。
