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acids and bases in solution

Added Apr 13, 2016 •

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alright see you studying chemistry what's the worst that can happen and most classes the worst that can happen is just abject total failure just like failing a test fail in the class how to get rethink your life choices Steven quit drop out of school get a job at a diner in start smoking Lucky Strikes chemistry the worst thing that can happen is death I don't want to make light of this labs are dangerous chemists die younger than the average person both because of workplace accidents and cancer caused by exposure to chemicals and Countess of also done more to increase the average lifespan of humans on Earth my opinion any other profession so it's a necessary Hazard last week we talked about stuff mixing together and that's important for sure but today and for the next few weeks we're going to talk about the axe reactions happening in those Solutions dangerous reactions atoms reorganizing themselves to create whole new substances are the processes that make our world the world do you know in love some of them are benign and beautiful some of them are face melting lead terrifying and that's not hyperbole I mean actual melted faces captain Mullen where he plays the first wagon trail across the Rocky Mountains into the interior of the Pacific Northwest right here for about 75 years and look what's happened to his face face reaction what are the three major types of reactions that happened in solution that will be talking about here crash course chemistry acid that did this was mostly sulfuric acid wondering who's been coming by and throwing sulfuric acid on statues actually what's been doing the throwing is clouds the sky though the actual source of the stearic acid that's 400 miles away at the Colstrip power plant in Colstrip Montana and also at coal-fired power plants all over the United States I'm cold for a year and most of that coal is mined right here in the u.s. Montana where I live is home to the Powder River Basin a geographical location coal output between 50 and 70 freight train soup out of the Powder River Basin everyday each train has at least 115 coal cars and is more than a mile and a half law how old is Cole burning it has effects significant effects acidic effects of first like what exactly are acids and bases placid's  shower  those are that's the first thing that we learned about acids actually and that's why acid actually means sour in Greek or Latin  Latin and acids are excellent at dissolving stuff until things have milk play what about bases you might have some idea of what is bitter tasting slippery like acid melt off your face acid basically in fact they're in antacids if you mix acids and bases together they neutralize each other things in chemistry in life when it comes right down to trying to find exactly what something is it gets weird and messy and confusing and terrible so forget everything you ever learned about acid wipe the Slate clean the most common acid on Earth is water and water is also the most common base and am I saying this feeling to confuse yes mostly to convince you that the world is way more complicated than you thought I was in 1923 two guys simultaneously defined acids and bases in the exact same bronsted and Lowry Define them they didn't classify them by how they acted or what they tasted like or even what they were made of they defined them and this was an impressive feat because a huge class of molecules to some extent or another act as acids and bases so they can put the definition that fit all of them that was not so simple an acid as being anything but donates a proton and a base as being anything but accepts a proton in water acids and bases can react in the gas but almost always there in an aqueous solution and when a proton gets donated in water it is accepted by water an H2 I was converted into h3o plus the hydronium ion so what acid is added to water it dissociates like any other ionic compound forming h3o + negative ion the acid has donated a proton to the water also a little chemistry terminology thing we usually just write H+ or same protons in solution when in we are referring to hydronium ions it's just a shorthand in reality H+ in aqueous solution is always h3o Plus acid for some more terminology bits here you see right off the bat that the HCL is donating a proton many assets particularly weak or acid the reaction can actually go back the other with h3o + donating its proton so when this situation every chemical in the reaction also sometimes called the major species can be called an acid or a base left hand side the water is accepting the proton so it's the base and HCL is donating it so it's the acid and on the left hand side the co- would be accepting the proton do the conjugate base in the hydronium ion is the conjugate acid acid always used to confuse me because I thought it had something to do with conjugating verbs actually the older sense of the word the one where conjugal or marriage-related visits for prisoners come from which means joined together for every acid there is a conjugate base and for every base there is a conjugate acid previous definitions of acids and bases particularly the one proposed by Don most notably our friend voh or hydroxide ion while hydroxide is in most cases it's not in all of them for example ammonia acts as a base when it reacts with chloric acid to form ammonium chloride there's no hydroxide but there is definitely proton donation and acceptance going on are not all created equal certain assets really like to get rid of their protons and will only reluctantly convert back from their con ticket Base by accepting the proton we call them strong acids and the comic is a weak base the same can be said for strong bases and acids the dihydrogen oxide is really great at being either a base accepting a proton from an acid or an acid donating a proton to a base plus where is the world's most common acid and also the most common base so what does any of this have to do with power plants in John Mullins face what was burned the sulfur in it reacts with oxygen to form sulfur dioxide that sulfur dioxide then reacts with water and oxygen in the air to form sulfuric when that sulfuric acid rains down instead of acid base reactions take place that damages Limestone and metal and acidifies the water supply making life harder for fish core salamanders and pretty much everything else is made of a chemical called calcium carbonate the car base accepting sulfuric acids protons and converting into carbonic acid the conjugate acid which breaks down into CO2 and water calcium and sulfate ions May precipitate as a salt that's more commonly known as gypsum okay the average ton of coal burned in America is about 3% sulfur of sulfur leave the smokestack and converts to sulfuric acid how much lime Stone could that completely wash away the units of sulfur X One Mall / 32.1 grams of sulfur to get 935 moles of sulfur in every ton of coal burnt that sulfur is can turn the H2 so4 and every mold that sulfuric acid react to the mole of limestone converting it to a mole of gypsum then that's 935 moles of limestone dissolved 100.1 G of calcium carbonate per mole if we multiply that by 935 moles we get 93600 G or 93.6 kg who eats ton of coal burnt by a us power plant produces enough sulfuric acid to dissolve about 94 kg of limestone and as we burn about a bill tons of coal per year it's safe to say that no statue is safe except for ones built of materials immune to acid particularly oxidized copper last pretty much forever hens lady Liberty's hand presiding over the Planet of the Apes so this is clearly a problem I mean not just for statues but acid rain has lower arm huge lots of forest at the peak of acid rain problems in the US the highest recorded acidity was around that of lemon juice which I can tell you is pretty acidic enough to irritate human skin this first became an issue for power generation when the British House of Lords in 1929 ruled that a power station was liable to damages caused nearby crops by acid rain so something had to be done but well we already know one very common chemical that reacts easily with sulfuric acid volume Stone and in England there is lots of limestone bypassing the smokestack gases through a limestone slurry the SO2 converts to an acid and then react put the Limestone forming Caso 3 calcium sulfate what's 3% sulfur coal is burned in America every year and all of it is converted to SO2 how many tons of limestone would we need to scrub out 100% of that so answers Down Below in the comments Limestone scrubber is a good system but it's not perfect many other flue gas desulfurization systems have been developed and now through a combination of good policy good science and hard work about 95% of sulfur produced in coal-fired power plants in the u.s. is removed before it leaves the smokes and threw some even smarter chemistry some of that SO2 is actually converted to Industrial useful chemicals for example pure sulfuric acid which is used in paper mills Iron and Steel making industrial cleaners and chemical synthesis causing problems but also fixing them I have learned that chemistry can cause death that acids and bases are more complicated than you thought they were and then an acid donates protons while the base accepts them you also should have learned put an acid donates a proton it forms account to get base and when a base donuts and protonic forms of conjugate acid also we did a little bit of acid based okiyama tree say was written by King Krieger and myself the script was edited by Blake dipastina and our chemistry consultant is dr. haikal langner cinematographer and editor is Nicholas script supervisor is Caitlin Hofmeister sound design by Michael LaRhonda and our Graphics team is thawed Cafe

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acids and bases in solution

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