评论
打印
This all happens in one step as the reaction is progressing
这些都发生在反应的这一步中
Here's what's happening
发生的情况是这样
This is the energy level of our reactants, A and B
这是反应物A和B的能级
When they react, they form C and D in its excited state
它们反应时，生成C和激发态的D
Now to relax back down to where it needs to be
之后D必须返回到基态
D emits energy as light
于是D会以光的形式释放能量
Now there's a different amount of energy in our reactants than our products
反应物和产物之间存在能量差异
So that's why these two energy levels are different
所以这两个能级是不同的
Alright, so in Dr. Dolhun's experiment
在Dolhun博士的实验中
each volunteer have a cup containing a different chemical
每位志愿者都拿着装有不同化学试剂的烧杯
and adds hydrogen peroxide to each cup
将另一个烧杯中的过氧化氢加入其中
And each cup glows a different color
每个烧杯发出不同颜色的光
red, blue, or green
红色，蓝色，绿色
This happens because the hydrogen peroxide is
这是因为过氧化氢
oxidizing each of the different chemicals
氧化了每一种化学试剂
So oxidation is the chemical reaction
这里发生的化学反应是氧化反应
that will ultimately cause the chemiluminescent
最终导致了化学发光
So why did each of these chemicals glow a different color?
为什么不同化学试剂会发出不同颜色的光呢
Well, it's because they each emitted a different amount energy
这是因为它们所释放能量的量不同
and energy equals color
而能量等于颜色
So let's think of it in terms of a rainbow spectrum
我们以彩虹光谱来考虑这个
So the amount of energy increases as you move up the spectrum
能量的量随光谱往上会逐渐增加
So red is lower energy than blue
红光的能量低于蓝光
So if the difference between the ground state and the excited state is small
如果基态和激发态之间的差异较小
there's a smaller amount energy released
释放的能量会较少
and the light is on the redder side of the spectrum
发出的光就会偏往光谱的红色方向
Conversely if that gap is larger, there's more energy released
相反，如果能差较大，释放的能量较多
so the light is on the bluer side of the spectrum
发出的光就会偏往光谱的蓝色方向
and this chemiluminescence chemistry has practical uses
这种化学发光具有实际用途
beyond glow sticks that light up a good party
不局限于派对上使用的荧光棒
We also use reactions like these to create flares that don't get too hot
我们还利用这样的反应来创造热量不高的闪光
in use of emergency situations
用于紧急情况
and nature uses chemiluminescence too
大自然也会使用这些化学发光
Have you ever seen a firefly light up at night
你们见过晚上飞舞的萤火虫吗
or an angler fish hunt for prey?
还有捕食猎物的琵琶鱼
You've seen bioluminescence
这些都是生物发光
which is chemiluminescence in a biological system
生物发光就是生物系统的化学发光
It's the exact same principle as the chemical reactions that Dr. Dolhun showed us
这同Dolhun博士所演示的化学实验是同一个原理
Hope you enjoy the video. I'll see you next time
但愿你们喜欢这个视频，我们下次再见
