把干冰放进液氮里安全吗？：英语精读讲义

When people started leaving comments asking me to mix dry ice with liquid nitrogen,

当大家开始留言让我把干冰和液氮混在一起时，

at first I thought it was a joke. 表達脈絡

起初我以为那只是个玩笑。

But then as the comments continued and continued and continued, 表達脈絡

但后来随着评论越来越多、越来越多，

I started to realize that this is a real thing. 短語搭配

我开始意识到大家是认真的。

So today, we're going to try mixing dry ice with liquid nitrogen

所以今天，我们要尝试把干冰和液氮混在一起，

just to satisfy your curiosity and see what happens. 短語搭配

纯粹为了满足你们的好奇心，看看会发生什么。

You already know that dry ice is just a solid chunk of carbon dioxide

你们已经知道，干冰只是一块固态二氧化碳，

that's extremely cold at minus 109 degrees Fahrenheit.

温度极低，只有零下109华氏度。

On the other hand, 表達脈絡

另一方面，

liquid nitrogen is just liquefied nitrogen gas.

液氮只是液化的氮气。

This stuff is minus 321 degrees Fahrenheit.

这东西是零下321华氏度。

This means the difference in temperature between dry ice and liquid nitrogen

这意味着干冰和液氮之间的温差，

is the same difference in temperature between boiling hot water

就像滚烫的开水

and a frozen chunk of ice.

和冻得硬邦邦的冰块之间的温差一样大。

For this experiment,

为了这个实验，

I've got the liquid nitrogen sitting in the thermos

我把液氮放在保温瓶里，

and that allows it to cool down to where it's happy and very calm. 講解

这样它就能冷却下来，保持在一个稳定、平静的状态。

So if we drop in a piece of dry ice now,

所以如果我们现在丢一块干冰进去，

what kind of reaction would you expect to take place? 短語搭配

你觉得会发生什么样的反应？

The liquid nitrogen boils

液氮沸腾了，

and the dry ice becomes even colder.

而干冰变得更冷了。

Let's just reach down in there and see if we can pull it out.

让我们把手伸进去，看看能不能把它捞出来。

Now the cool thing about this dry ice,

这块干冰很酷的一点是，

it has been cryogenically reduced to the temperature of liquid nitrogen. 用詞

它已经被极低温冷却到了液氮的温度。

So instead of being minus 109 degrees Fahrenheit, 語法

所以，这块干冰现在不再是零下109华氏度，

this block of dry ice is now about minus 321 Fahrenheit.

而是大约零下321华氏度。

This is amazing.

太神奇了。

It's actually boiled out most of the nitrogen. 短語動詞

它其实已经把大部分液氮都煮沸挥发了。

Which of these do you think is more dense?

你觉得这两个哪个密度更大？

Dry ice or liquid nitrogen?

干冰还是液氮？

In other words, 表達脈絡

换句话说，

if I drop dry ice into a glass of liquid nitrogen,

如果我把干冰丢进一杯液氮里，

will it sink or will it float?

它是会下沉还是漂浮？

I don't see it floating on the top there.

我没看到它漂在表面上。

Let's add a few more chunks just to be sure. 短語搭配

为了确认，我们再多加几块。

Yep,

是的，

I can hear that sinking right to the bottom.

我能听到它直接沉底的声音。

It's really cool how it mists for just a second

冒出一秒钟的雾气然后完全消失，这真的很酷，

and then the mist completely disappears

接着雾气彻底消失，

and that's because the liquid nitrogen is cooling the dry ice down 表達脈絡

这是因为液氮正在把干冰降温

to cryogenic temperatures.

到极低的温度。

So we can see that dry ice is more dense than liquid nitrogen

所以我们可以看出干冰的密度比液氮大，

because it sinks to the bottom.

因为它沉到了底部。

Care for a cold drink? 語氣意圖

来杯冷饮吗？

Cheers.

干杯。

Just joking,

开个玩笑，

just joking.

只是开个玩笑。

For this experiment,

为了这个实验，

I have two identical bowls of water

我准备了两个一样装满水的碗，

and two identical chunks of dry ice

还有两块一模一样的干冰，

except one's been soaked in liquid nitrogen, 語法

唯一的区别是一块泡过液氮，

the other one hasn't.

另一块没有。

If we drop them at the exact same time into two separate dishes, 語法

如果我们同时把它们分别放进两个碟子里，

how are they going to react?

它们会产生怎样的反应？

You can see that both two bowls are reacting about the same.

你能看到两个碗里的反应差不多。

They're producing the same amount of vapor, 短語搭配

它们产生的雾气量相同，

they're bubbling at about the same rate. 短語搭配

冒泡的速度也差不多。

They're both popping off cool little smoke rings

它们都吐出了酷酷的小烟圈，

which is like my favorite part.

这简直是我最喜欢的部分。

That doesn't really surprise me so much.

这并不让我感到意外。

The question is going to be which one lasts longer? 表達脈絡

问题在于，哪一个能持续更久？

Will the colder block of dry ice outlast the untreated piece?

更冷的这块干冰会比没处理过的那块撑得更久吗？

Now this has been running for about five minutes 語法

现在这已经进行了大概五分钟了，

and you can see the bowl with the liquid nitrogen treated dry ice

你可以看到，装有液氮处理过的干冰的那个碗，

actually still has a thicker vapor.

依然有着更浓厚的雾气。

There was enough cold in the first bowl

第一个碗里积攒了足够的冷气，

to keep the reaction going a little bit longer. 短語搭配

使得反应能多持续一会儿。

We all know that when you drop dry ice into water,

我们都知道当你把干冰丢进水里时，

it forms an amazing misting fog

它会产生神奇的烟雾，

that just seems to flow out of the water.

像是从水里流出来一样。

So will it do the same thing with liquid nitrogen?

那么它在液氮里也会有同样的效果吗？

For this first experiment,

对于这第一个实验，

let's drill two holes

我们钻两个洞

into the same block of dry ice.

钻在同一块干冰上。

We'll put liquid nitrogen in one hole

我们在一个洞里倒液氮，

and water in the other

另一个洞里倒水，

and observe the results.

然后观察结果。

All right,

好了，

here we go,

我们开始了，

liquid nitrogen.

倒液氮。

It's amazing to think about

想想真是奇妙，

but the dry ice is actually so hot right now 語法

但这块干冰现在对它来说其实非常热，

that when we add the liquid nitrogen,

以至于当我们加入液氮时，

it boils it and vaporizes it in just an instant

液氮会在瞬间沸腾并气化，

and that's why we're getting the fog flowing off that we are.

这就是为什么我们会看到冒出这么多的烟雾。

All right,

好了，

we got that thing chock full of liquid nitrogen. 習語

我们把那个洞装满了液氮。

Let's add water to the other side

我们在另一边加水，

and observe the difference.

看看有什么区别。

Oh,

哇，

that's so cool.

真酷。

Our block of dry ice is blowing smoke rings.

我们的干冰块在吐烟圈。

Now if you notice the liquid nitrogen is completely vaporized.

现在你注意看，液氮已经完全气化了。

Dry ice is so cold it'll freeze water solid 講解

干冰极冷，能把水冻成固体，

but at the same time it's so hot it'll boil off liquid nitrogen. 短語動詞

但同时它也够热，能让液氮沸腾蒸发。

All water does is cool down to the point 講解

水只是冷却到一个临界点，

where it would eventually crystallize and turn into ice.

最终结晶变成冰。

That's how you make carbonated ice cubes.

碳酸冰块就是这么做出来的。

This is a reaction I didn't expect. 語法

这是一个我没预料到的反应。

Here's a regular chunk of dry ice.

这是一块普通的干冰。

Try punching that 語法

试着用力捶它一下，

and you end up with sore knuckles. 短語動詞

你的指关节会疼。

Soak the dry ice in liquid nitrogen

但把干冰浸泡在液氮里，

and it pulverizes without problem.

就能轻而易举地把它粉碎。

I was not expecting that.

我真没想到会这样。

That's cool.

太酷了。

I'm going to do that again.

我要再试一次。

Okay,

好了，

let's go throw this stuff in the bathtub.

我们去把这东西扔进浴缸里吧。

This dry ice has just been frozen in liquid nitrogen. 語法

这块干冰刚刚在液氮里被冷冻过。

We're going to throw it into the tub

我们要把这东西扔进这里的浴缸里，

here and see what happens.

看看会发生什么。

Okay,

好吧，

that was cool

这挺酷的，

but it feels a little bit weak. 語氣意圖

但感觉效果有点弱。

Let's dump the rest of it in there.

我们把剩下的都倒进去。

This is cool.

这太酷了。

Our bathtub has just disappeared.

我们的浴缸完全不见了。

It like stings your face when you breathe it. 語氣意圖

呼吸时它会有点刺痛你的脸。

So what happens when you dip dry ice in liquid nitrogen?

那么当你把干冰泡在液氮里会发生什么？

Well,

嗯，

you get a pretty cool reaction

你会得到一个非常酷的反应

and very, very cold dry ice.

还有非常、非常冷的干冰。

So there you have it, 習語

这就是全部内容了，

guys.

伙计们。

Now you know what happens if you put dry ice in liquid nitrogen.

现在你知道把干冰放进液氮里会发生什么了。

Thanks for joining me for this experiment today. 短語搭配

感谢今天陪我做这个实验。

I'll be looking for you in the next video.

我们下个视频见。

Talk to you then.

到时见。

And then threw the whole batch into a bathtub

后来我把一整批干冰扔进了一个浴缸，

full of extremely warm water.

里面装满了非常热的水。

Oh,

哇，

dude.

老兄。

Look at the way that shattered. 語法

看看它是怎么碎开的。

Apparently, 語氣意圖

显然，

liquid nitrogen frozen dry ice

被液氮冷冻过的干冰

becomes a lot more brittle as well. 語法

也会变得脆弱得多。

Woah!

哇！

Oh my goodness.

我的天啊。

Okay,

好吧，

that's worthy to note.

这点值得注意。