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Hi, I'm Jessica
嗨，我是Jessica
And today I'm going to shed some light on a chemical demonstration
今天我要讲的化学演示
I like to call "anatomy of a glow stick"
叫作"荧光棒解剖"
There are many different kinds of chemical reactions
化学反应有很多种
Some absorb energy and some release energy
有一些需要吸收能量，有一些则会释放能量
Some release energy as heat and others as light
释放能量的形式有时是热，有时是光
and when a reaction produces light
当反应生成光时
the process is called chemiluminescence
这个过程就叫作化学发光
Let's watch MIT's Dr. John Dolhun
下面来看MIT的John Dolhun博士
his assistant Shannon
他的助手Shannon
and volunteers Sarah, Catherine, and Trevor
以及志愿者Sarah Catherine和Trevor
They're gonna show us some chemiluminescence at the Cambridge Science Festival
在剑桥科学节上演示化学发光
So not all reactions have this ability to produce lights
并非所有化学反应都能产生光
So we have to use some very special chemicals in order to do this
为了实现这个目的，需要非常特殊的化学试剂
And we have some light sticks that I broke apart here
这里我破开了一些荧光棒
If you guys just want to take these solutions
请你们拿着这些溶液
hold them carefully
小心拿着
And so in a light stick
荧光棒中
usually there's actually hydrogen peroxide
通常会有过氧化氢
and it oxidizes different chemicals --
它能氧化不同化学试剂
Please face the audience. That's cool
请对着观众，这很酷
and it'll oxidize different chemicals
它能氧化不同化学试剂
depending on what color you want to give a light
取决于你想要什么颜色的光
Alright, just pour one solution to the other. It doesn't matter which way
好，请将一种溶液倒入另外一种中，两种方式都行
And there we go, okay
有了，很好
Beautiful, beautiful, alright
很美丽，很美丽，好
So in each of these, we have a different chemical that gets oxidized
这每一个反应中，都有不同化学试剂被氧化了
to give us a different color
从而得到了不同颜色
Alright, thank you guys so much
好，非常感谢你们
So how does a reaction produce light?
反应是如何发光的呢
Let's start with two molecules. Let's call them A and B
首先是两种分子，分别记作A和B
They react to produce C and D
它们反应生成C和D
Energy that's produced in the reaction
反应中生成的能量
causes the electrons in D to become excited
导致D中的电子被激发
As the electrons relax back down, they give off energy as light
随着电子返回基态，它们会以光的形式释放能量
So basically chemical energy is transformed into light energy
化学能被转化为了光能
