Name: Arsenic (new) - Periodic Table of Videos
Uploaded: 2020-03-27T18:39:00.000Z
Duration: 18 min 11 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

we're going to tell you about the chemistry of our snake.

It has some very nice connections with ancient wallpaper on dhe.

Neil is going to show you a whole series of experiments.

Oh, the books say that our snake looks metallic that our sample looked a bit brown, so new heated it in a test tube.

The vapor is formed and condenses on the side of the vessel.

And if you look carefully, you can see it makes a very nice metallic film.

Our snake is particularly famous as a poison.

People used it to get rid of their lovers, their wives, or just talk with people.

And the compound they used is arsenic oxide A S 406 Now we didn't have a sample of this, so we decided that Neil would make some forests.

So he began by dissolving all snick in dilute nitric acid.

There's quite a violent reaction, lots of bubbling and it forms the gas N o nitric oxide which is colorless.

But it reacts with air to give nitrogen dioxide, which is brown, so you can see brownish fumes coming out with the test tube.

The takes books say that when you dissolve our snake in nitric acid, you make a solution off the oxide.

Pour the solution in and it came through.

There must say it did still look a little brown, but we were really hopeful we were going to get our white powder.

The next stage, of course, is to go from solution to solid, so you have to evaporate off the water.

I got bored and went out while Neil was finishing it.

Instead of this lovely white powder, there was some sticky brown solid, I presume, because we've still got some particles of arsenic in the white powder.

At least we tried, but I still think it's probably our snake oxide.

The reason they used arsenic oxide, which they could easily get it.

It tasted sweet, so it wasn't very noticeable if you mixed it with sugar.

So our brown stuff is not going to be much use for poisoning people.

I have two favorite stories about poisoning.

The 1st 1 happened in a town in the north of England called Bradford.

In those days, sugar was quite expensive, so people who made sweets were very dishonest and added some cheap powder to the sugar so that they didn't have to put so much sugar in the sweets.

On this particular occasion, a sweet maker called Jon Neal sentence his lodger to go and get some daft to put in his next batch of sweets.

He called them lots inches, and he went to the next town on DDE, went to a pharmacist, and the pharmacist told his assistant to go and fetch the deft, which was the white powder.

And unfortunately, he didn't explain correctly.

That's five kilos off arsenic oxide to the unfortunate customer.

This was mixed in with the sweet mixture on dhe, more than 20 people died of arsenic poisoning in Bradford, and more than 200 were really ill.

And this was one of the things that led to a greater control of arsenic in the United Kingdom.

The other case took place in the early 19 twenties in the town in the west of England called Hay on Wye.

The attacks were carried out by a solicitor, a lawyer, who in fact was the only lawyer who's ever been hanged in the UK It is believed he poisoned his wife with our snake over a period of several months, and then one of his business rivals was invited to tea.

The lawyer passed a scar on a little cake in his fingers to his rival, and as he passed it, he said, Excuse fingers, and in that moment it is believed he put arsenic on the cake.

Dhe was found to have been poisoned with arsenic, so they exhumed the body of his wife, dug it up and it was full of arsenic.

So he was tried on Dhe, convicted and executed, and that should be said that he always denied that he had done this that when he was arrested, he did have all snick powder in a packet in his pocket that he had good white powder.

Our brands, like he had nice white powder.

The question is, how did they find our snake in the body of his dead wife, who had been under the ground for several months?

And it's with a very clever test that was invented in the early 19 century cold marshes test on Neil decided he would like to do marshes test to the first thing you have to do.

You put in the pieces of sink into round bottom flask, and then you add whatever you think contains arsenic in our case, a small amount of Neil's brown sludge and then from a dropping funnel.

You drop in, dilute sulfuric acid on the sulfuric acid, reacts with the sink and generates hydrogen on the hydrogen, reacts with the arse nick and makes a compound which has a similar formula.

But it has three hydrogen sze attached arsenic rather than three hydrogen sze attempts to nitrogen, which you have in ammonia on this compound called our scene his very volatile.

As the hydrogen streams off the reaction, it takes the whole scene with it.

You're then meant to light the stream of hydrogen coming out of the nose along the top of the apparatus.

If it's just hydrogen coming out, it would be colorless.

And Brady was absolutely convinced that we would see a colors list flame, and he could tell us how bad we've bean at the experiment.

The flame came out a beautiful lavender color.

Lavender is the color that arse Nick Burns with, but the rial elegance of marshes test is that if you put a cold surface, a piece of glass or a piece of porcelain into the flame wth E, I'll seen does not burn completely.

So you get a thin film off arse Nick on the surface.

The importance of this was that once the films there, it will stay there so it could be taken to court to be shown as a piece of evidence, and you could say, Look, arse Nick came out of the woman's stomach or whatever the sample was that you had.

There's another, completely different way that people in the 19th century were poisoned by arsenic, and that was from the green coloring, the green pigment that was used in their wallpaper.

This green pigment is a cop assault called Sheila's Green.

It is made by taking a solution of sodium meta last night, which is colorless and dropping in copper sulfate, which is blue.

I've done this reaction several times, but I haven't done it for a long time, and I was really surprised quite how beautiful it is, saying this green solid, forming sealers green was used quite widely.

This would be fine, except in those days people were really frightened of drafts on.

They usedto close all the windows and doors and have very stuffy rooms, which were not very well heated.

So particularly at night when they were asleep, there was a lot of condensation, and mold would grow on the wallpaper.

And so the mold growing on your wallpaper could create a gas containing arsenic, which, if you were lying asleep in this airless room over a period of just one night would be enough to kill you.

In October 18 15 Napoleon Bonaparte was brought a prisoner to the island of Santa Lena in the South Atlantic.

Yeah, he was to spend the last six years of his life here.

Examination was made of specimens of hair sitio being taken from the head of Napoleon both before and after he died.

Results established the presence of arsenic.

My friends, David Jones, who was an expert in really weird chemical facts, wondered whether the stories of Napoleon being poisoned with arsenic by the wicked British could in fact be due to mold on the wall paper into his house on the island of ST Elina, where he was exiled.

Remarkably, David managed to get hold of a sample off Napoleon's wallpaper, which had some green marks on it.

Andi, He could analyze this and show that it did indeed contain arsenic, and there was enough else Nick and Napoleon's wallpaper to explain the arsenic that had been found in his hair but not enough to have killed him.

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Arsenic (new) - Periodic Table of Videos

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