today I'm going to make a car that runs on water and also investigating whether cars that run on water could actually be worse for the environment than a traditional gas engine of all the molecules on the planet water is the molecule that almost everyone knows do you know what water's made of H2O yep water is made of two atoms of hydrogen in one atom of oxygen so that means when you burn hydrogen gas in air it'll make a pretty good explosion as it reacts with the oxygen in the air to make water okay here we go so we did see a puff of fire but that's a pretty lame explosion if you ask me the reaction didn't happen very fast because the hydrogen had to mix with the oxygen in the air before it could react but if instead of filling a bubble with pure hydrogen I fill it instead with hydrogen gas mixed with oxygen gas in a 2:1 ratio you get something that can be quite dangerous okay here we go this mixture of gases is called a stochiometric oxyhydrogen gas holy cow it's hard to tell how loud this actually is because it Clips the sound on the audio track so let me put my deciel meter here so we can see how loud it actually is 112.8 DB from a little bubble like this that's as loud as standing about 100 ft away from a jet engine the speed of detonation is about 3,000 m/ second about 8 times faster than the speed of sound and about six times faster than the detonation of gunpowder there's a lot of power packed into this gas and when it releases that power it's intense but what if we didn't have to release the power all at once What If instead of all the hydrogen reacting with all the oxygen at one time they could take turns and make a nice controlled reaction for example I have two tanks of gas under this water here one is hydrogen and the other is oxygen the gases are going to combine in a controlled reaction in this contraption called a fuel cell to make water and when they combine we get some energy out of it only we don't get uncontrolled pressure spikes and a lot of heat but we get electricity okay so I'm just going to touch these two electrodes to the motor wires in the back here so this is literally only being powered by these gases here in fact if you watch it long enough you'll see that the volume of those gases are decreasing as this motor spins I can use this electricity to power a fan or even power a car motor for example I can make a little benchtop model of a car that's powered by these gases I put the tanks of gas on the back and when I connect the electrodes the car starts moving so it's an electric car that's powered by gas only these wheels don't turn very well this is called called a hydrogen fuel cell car and you can make fulls scale cars that work just like this in hydrogen fuel celled cars they store hydrogen in a high press tank that's then fed to the fuel cells in the car that generate electricity when the hydrogen reacts with the oxygen in the air but how do you get electricity from two gases reacting together well electrons are attracted to oxygen more than they're attracted to hydrogen due to the fact that oxygen has eight positive protons that aren't shielded that much from it surrounding electrons so if possible it'll pull the electrons off of a hydrogen atom and the hydrogen and oxygen will end up sharing with the majority of the electron being near the oxygen and that's exactly what's Happening Here the oxygen on this side of the fuel cell is touching the Platinum metal that's connected through the wires to the metal on the other side that's touching the hydrogen gas so the oxygen can literally pull the electrons off of the hydrogen on the other side and so we just make use of the movement of electrons through the wires instead of just letting them go right to the oxygen we make them pass through this wire and do some work along the way so we did the exact same reaction that happened with the explosion but just in a much more controlled way so a hydrogen fuel cell can make water from oxygen and hydrogen but it can also make hydrogen and oxygen from water if you put in power so if I just run power to these two electrodes I can immediately start generating hydrogen and oxygen and that hydrogen and oxygen can then be used to turn a motor later when I need need it so I now have a car that runs on water alone and before we continue when life gets more difficult than chemistry it's nice to know that there's help out there so I want to take a minute to thank the sponsor for this video better help these last few years have been difficult for everyone and one of the most important things you can do in times like this is to focus on your mental health better help is the world's largest therapy service and it's 100% online with better help you can tap into a network of over 30,000 licensed and experienced therapists who can help you with a wide range of issues to get started you just answer a few questions about your needs and preferences in therapy that way better help can match you with the right therapist from their Network then you can talk to your therapist however you feel comfortable whether it's via messaging phone or video call you can message your therapist anytime and schedule a live session when it's convenient for you and if your therapist isn't the right fit for you for any reason you can switch to a new therapist at no additional charge as well with better you get the same professionalism and quality you expect from in-office therapy but with a therapist who's custom picked for you more scheduling flexibility at a more affordable price so get 10% off your first month at betterhelp.com actionlab or you can click the link in the description and thanks for better help for sponsoring this video now let's get back to our experiment now at this point your thermodynamic energy balance senses should be tingling right now is the car actually running on water well if you turn to fill good news stories then yes you can get cars to run on water oh this is nice some kid in India created a motorbike that runs on water alone it says it looks like they're using the same thing we did here he uses the battery from his bike to split the water into hydrogen and oxygen and then burns the oxyhydrogen fuel how have we missed this technology all these years oh look another YouTube video that has 1.4 million views they use the battery to split water into this flammable mixture of hydrogen and oxygen and then they use that to power the motor then turns the alternator to charge the battery that keeps splitting the water into hydrogen and oxygen what a great idea only there's one problem here it doesn't work let's see how much energy it takes to split this water into hydrogen and oxygen it took me 8 seconds to make 10 mL at 5 amps and 3.5 Vol so that's 140 jewles it took me 100 seconds to use 10 millit at .5 volts in 0.5 amps so that means I only got 25 jewles of energy back out of it so in this case right here I only got a fifth of the energy out that I put into it so it took me more energy to split the water than we got back out of it when we combine the hydrogen and oxygen back together so this video is a big fat lie and surprisingly no one seems to know it in the comments section you can't use water as a fuel because the water is the product of the reactants it doesn't have any chemical energy to give any video or news story that talks about using water to power a vehicle always uses some energy source to make fuel from water and then uses that fuel to power the vehicle you can use metals that react to form hydrogen from water or you can you just use electrolysis from a battery that was charged using some other fuel but no matter what it costs more energy to split water apart than you'll ever get back out of it when you burn it back together again but what about if we just use the energy from the Sun to split the water well in that case it would work but you still aren't using the water as the fuel the sun is the fuel this is why a few years years back hydrogen fuel cell cars seem like they'd be a great Alternative Energy car for the future all you need is a tank of hydrogen and you can power your car this hydrogen can be produced from alternative energy sources like the sun water or wind but the problem is that most of the hydrogen in the world isn't produced through electrolysis from these alternative energy sources most of the hydrogen in the world is made by reacting natural gas with steam by heating it up so you burn hydrocarbons to heat up the process and then you use hydrocarbons to make the hydrogen gas so by making this clean hydrogen gas that can be used to power an engine that makes nothing but water is the exhaust you created a whole bunch of CO2 in the process in fact hydrogen production makes about 830 million tons of CO2 annually that's more CO2 than you would have released if you just burned the natural gas that was used to make the hydrogen gas in the first place so cars that run on hydrogen seem like a really good idea in theory but in reality they're doing more harm than good unless they're truly using renewable energy but I don't want to Discount hydrogen fuel cells too much they're still a really cool technology and since electricity can be used to make the hydrogen these hydrogen fuel cells still could be of potential use if or when we start using nuclear power as our main source of energy and thanks again for watching the action lab and we'll see you next time