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  • (Intro)

  • (Warning)

  • Hello everyone! Today I want to tell you about such element as oxygen

  • and show its properties along the way.

  • I think many of you already know that oxygen resides in the atmosphere and is essential for life,

  • and is also involved in the combustion process, i.e. oxidation.

  • Oxygen is the most abundant element on Earth, our atmosphere contains only 21% of oxygen.

  • The remainder of the oxygen on Earth is distributed in the form of compounds - that is

  • oxides, carbonates and water.

  • We have all seen that lots of different things can burn down in oxygen such as wood, paper and plastic.

  • Though if we increase the oxygen concentration then things start to burn quite more intensely.

  • Also, like any gas, oxygen can be condensed, i.e. liquefied.

  • For the condensation of liquid oxygen we've used liquid nitrogen.

  • The boiling point of liquid nitrogen is 13 degrees lower than that of oxygen, so

  • by passing pure oxygen from a cylinder through a copper coil that is cooled by liquid nitrogen we can obtain liquid oxygen.

  • The oxygen liquefaction itself looks very fascinating.

  • (it's so beautiful)

  • Fun fact - in large hospitals oxygen is normally stored in

  • liquid form in large tanks to save space and for easy transportation.

  • And we've obtained the liquid oxygen, let's look at its properties.

  • The most interesting fact is that in liquid state oxygen is not a transparent liquid, it's in fact blue!

  • All because of the light absorption spectrum of oxygen atoms.

  • Also, liquid oxygen is paramagnetic and is attracted to magnets,

  • by looking closer we can see small droplets rising towards the magnet.

  • For the experiments with oxygen, we took a sponge,

  • toilet paper,

  • chips,

  • tea,

  • T-shirt,

  • crackers

  • and a few other items.

  • To begin, we take a dry crust of white bread and try to burn it at normal oxygen concentration in the air.

  • As expected, the bread does not want to burn.

  • Now let's soak it with liquid oxygen and try to ignite it again.

  • (rip bread)

  • The liquid oxygen dry bread turned into a real jet cracker...

  • ...even gave little traction.

  • If we add some more oxygen to the smoldering cracker it starts to burn again.

  • Now let's take a toilet paper and soak it in liquid oxygen and then set it on fire.

  • (rip toilet paper)

  • I think we have just created a new kind of rocket fuel out of toilet paper.

  • In fact, in the rocket engines of Shuttle liquid oxygen served as an oxidant and liquid hydrogen was the fuel.

  • Unfortunately, we don't have any liquid hydrogen, however, look at this lovely tea bag!

  • In the cup filled with liquid oxygen it doesn't want to brew (meaning we won't have any liquid oxygen tea today),

  • however in the subsequent ignition it then turns into a real powder.

  • (rip tea bag)

  • Also, if you soak a cotton T-shirt in liquid oxygen and ignite it,

  • it will turn into a real bomb!

  • (rip T-shirt)

  • DO NOT ATTEMPT TO REPEAT WHAT YOU HAVE JUST SEEN!

  • From the close contact of oxygen molecules with the T-shirt material, its combustion is magnified.

  • The same thing happens with a cotton wool...

  • (rip cotton wool)

  • ...as it absorbs oxygen very well and has a large surface area of the particles.

  • Though the most rapid combustion reaction with liquid oxygen was acquired with an ordinary kitchen sponge.

  • (rip kitchen sponge)

  • The soaked in liquid oxygen sponge simply disappeared when it was ignited without even leaving a piece of it as a memory.

  • If you like chips, think of how bad they can be for your health, how much fat and harmful substances is contained in them.

  • It is better to throw them away, but wait, they contain a lot of energy!

  • With the addition of liquid oxygen all the energy contained in those chips breaks out in seconds.

  • (rip chips)

  • During the combustion of chips, as well as everything before them, carbon dioxide is formed and hydrogen monoxide (which is water in the form of steam).

  • Also, for those who don't have strong positive feelings

  • towards oat porridge,

  • we have specially soaked it in liquid oxygen for you, and ignited it to show you how much energy it contains!

  • Oatmeal is not only full of beneficial vitamins and minerals,

  • but it also energizes you for the whole day!

  • Also, if we lower burning sulfur into a flask with liquid oxygen,

  • it will light with a very beautiful blue flame. It looks absolutely glorious.

  • As a result of this reaction, oxygen and sulfur have formed sulfur dioxide.

  • And finally, we decided to burn iron.

  • Everyone knows that iron does not burn in air.

  • But if you make it into more like thin chips of wool,

  • and set on fire, it will burn well.

  • What can we say about liquid oxygen?

  • Adding steel wool to it will make it a real lava - burning in seconds and turning into iron oxide.

  • From the heat of the reaction, the steel saucer even melted.

  • Oxygen in nature typically exists in gaseous form and in low concentrations that save us all from the fire randomly appearing everywhere

  • if there would be more oxygen.

  • Oxygen has a two-atom molecule, but there is one other molecule that consists of 3 oxygen atoms!

  • That is ozone.

  • Such a phenomenon is called allotropic modification.

  • In the troposphere, we don't have much ozone.

  • and it's mainly found on a higher altitude.

  • The ozone layer protects us from the strong ultraviolet radiation coming from the sun.

  • Without it, our eyes would have ceased to see in a couple of hours.

  • The retina would have simply been burned and life on Earth would be pretty much impossible.

  • Also the molecules that make up our body contain a lot of oxygen. In our body, it has the most presence if we compare it by mass.

  • Oxygen is produced from photosynthesis in plant cells.

  • Think about it before cutting down the trees!

  • If you would like to support the continuous production of science videos like this one, please support channel on Patreon - link in the video description.

  • Please like this video and subscribe to my channel to see many more of new and interesting!

  • (Outro and Thoisoi's cat)

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Oxygen - The MOST ABUNDANT Element On EARTH!

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    Wongwl   に公開 2018 年 01 月 10 日
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