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(Intro)
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(Warning)
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Hello everyone! Today I want to tell you about such element as oxygen
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and show its properties along the way.
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I think many of you already know that oxygen resides in the atmosphere and is essential for life,
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and is also involved in the combustion process, i.e. oxidation.
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Oxygen is the most abundant element on Earth, our atmosphere contains only 21% of oxygen.
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The remainder of the oxygen on Earth is distributed in the form of compounds - that is
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oxides, carbonates and water.
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We have all seen that lots of different things can burn down in oxygen such as wood, paper and plastic.
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Though if we increase the oxygen concentration then things start to burn quite more intensely.
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Also, like any gas, oxygen can be condensed, i.e. liquefied.
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For the condensation of liquid oxygen we've used liquid nitrogen.
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The boiling point of liquid nitrogen is 13 degrees lower than that of oxygen, so
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by passing pure oxygen from a cylinder through a copper coil that is cooled by liquid nitrogen we can obtain liquid oxygen.
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The oxygen liquefaction itself looks very fascinating.
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(it's so beautiful)
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Fun fact - in large hospitals oxygen is normally stored in
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liquid form in large tanks to save space and for easy transportation.
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And we've obtained the liquid oxygen, let's look at its properties.
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The most interesting fact is that in liquid state oxygen is not a transparent liquid, it's in fact blue!
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All because of the light absorption spectrum of oxygen atoms.
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Also, liquid oxygen is paramagnetic and is attracted to magnets,
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by looking closer we can see small droplets rising towards the magnet.
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For the experiments with oxygen, we took a sponge,
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toilet paper,
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chips,
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tea,
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T-shirt,
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crackers
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and a few other items.
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To begin, we take a dry crust of white bread and try to burn it at normal oxygen concentration in the air.
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As expected, the bread does not want to burn.
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Now let's soak it with liquid oxygen and try to ignite it again.
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(rip bread)
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The liquid oxygen dry bread turned into a real jet cracker...
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...even gave little traction.
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If we add some more oxygen to the smoldering cracker it starts to burn again.
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Now let's take a toilet paper and soak it in liquid oxygen and then set it on fire.
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(rip toilet paper)
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I think we have just created a new kind of rocket fuel out of toilet paper.
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In fact, in the rocket engines of Shuttle liquid oxygen served as an oxidant and liquid hydrogen was the fuel.
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Unfortunately, we don't have any liquid hydrogen, however, look at this lovely tea bag!
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In the cup filled with liquid oxygen it doesn't want to brew (meaning we won't have any liquid oxygen tea today),
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however in the subsequent ignition it then turns into a real powder.
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(rip tea bag)
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Also, if you soak a cotton T-shirt in liquid oxygen and ignite it,
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it will turn into a real bomb!
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(rip T-shirt)
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DO NOT ATTEMPT TO REPEAT WHAT YOU HAVE JUST SEEN!
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From the close contact of oxygen molecules with the T-shirt material, its combustion is magnified.
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The same thing happens with a cotton wool...
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(rip cotton wool)
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...as it absorbs oxygen very well and has a large surface area of the particles.
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Though the most rapid combustion reaction with liquid oxygen was acquired with an ordinary kitchen sponge.
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(rip kitchen sponge)
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The soaked in liquid oxygen sponge simply disappeared when it was ignited without even leaving a piece of it as a memory.
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If you like chips, think of how bad they can be for your health, how much fat and harmful substances is contained in them.
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It is better to throw them away, but wait, they contain a lot of energy!
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With the addition of liquid oxygen all the energy contained in those chips breaks out in seconds.
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(rip chips)
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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).
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Also, for those who don't have strong positive feelings
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towards oat porridge,
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we have specially soaked it in liquid oxygen for you, and ignited it to show you how much energy it contains!
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Oatmeal is not only full of beneficial vitamins and minerals,
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but it also energizes you for the whole day!
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Also, if we lower burning sulfur into a flask with liquid oxygen,
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it will light with a very beautiful blue flame. It looks absolutely glorious.
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As a result of this reaction, oxygen and sulfur have formed sulfur dioxide.
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And finally, we decided to burn iron.
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Everyone knows that iron does not burn in air.
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But if you make it into more like thin chips of wool,
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and set on fire, it will burn well.
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What can we say about liquid oxygen?
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Adding steel wool to it will make it a real lava - burning in seconds and turning into iron oxide.
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From the heat of the reaction, the steel saucer even melted.
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Oxygen in nature typically exists in gaseous form and in low concentrations that save us all from the fire randomly appearing everywhere
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if there would be more oxygen.
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Oxygen has a two-atom molecule, but there is one other molecule that consists of 3 oxygen atoms!
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That is ozone.
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Such a phenomenon is called allotropic modification.
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In the troposphere, we don't have much ozone.
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and it's mainly found on a higher altitude.
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The ozone layer protects us from the strong ultraviolet radiation coming from the sun.
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Without it, our eyes would have ceased to see in a couple of hours.
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The retina would have simply been burned and life on Earth would be pretty much impossible.
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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.
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Oxygen is produced from photosynthesis in plant cells.
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Think about it before cutting down the trees!
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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.
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Please like this video and subscribe to my channel to see many more of new and interesting!
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(Outro and Thoisoi's cat)