Can someone please explain how this fuel cell works...?
454802
it's basically from the movement of electron transfer from one of the metal to the other. to know the flow of electrons from which metal to which, u need to know their standard reduction potentials
809942
Here is an idea.\nCompare power supplies by weight, volume and power density using various batteries.\n\nThere are many batteries on the market now, so it might be very educational for you and anyone looking at your project.\n\nConsider using the following batteries:\nLead acid battery\nLithium-ion battery\nLithium ion polymer battery\nNickel-cadmium battery\nNickel metal hydride battery\nMolten salt battery\nSilver-oxide battery\nWater-activated batteries used in radiosondes\n\nYou could compare different AA batteries of different types and costs.\n\nA good starting point for references on batteries is on Wikipedia:\nhttp://en.wikipedia.org/wiki/Batteries\n\nYou might even be able to get a small prototype fuel cell if you ask to work with a battery manufacturer, a research company, or someone like NASA.\n\nYou should start thinking of what kind of a hypothesis you could write to kick of the experiment.  Hint: Don't worry if your experiment fails and you fail to prove your hypothesis. Sometimes the best experiments are failures!\n\nHope this helps!
95444
Some tips...\n--Use a strong electrolyte (substances that will break up into ions [almost] completely in solution), the higher the concentration, the better.  Also you need to be careful on which electrolyte you choose.\n--Try not to use an over volttage (a voltage over the minimum necesary to electrolisize the water.  Insread, try to use a very high current, higher current = more production of gasses.  To increase current without increasing voltage, reduce resistance.\n--Place the electrodes close together to reduce internal resistance in the cell.\n\nEven by doing these things, you cannot hope to get much better than about 50% efficency doing water electrolysis, maybe 65% if you are good.\n\nThere are yahoo groups out there devoted to just such a tast as Hydrogen production through water electrolysis (I have one infact), they can also give advice based on experience.
372993
If you mean the decomposition of a chemical (electrolyte) by the passage of an electric current, you just get two electrodes (pieces of metal) that won't be attacked by the chemical or its electrolysis products and stick them in the electrolyte, and then connect the electrodes to a source of electrical current. You have to experiment with the voltage to be sure it is enough to produce electrolysis at a reasonable rate. If you want to collect any gaseous products of electrolysis, you can let the gas bubble up into an inverted container that is initally filled with the electrolyte. \nElectroplating (ref.) is a related phenomenon. In this case one electrode, connected to a negative voltage, is the metal item you want to receive the plating and the other, connected to a positive voltage, is the metal that provides the plating. The electrolyte is a water solution of a salt of the plating metal.
931534
According to Alex Imholtz ( http://www.otal.umd.edu/~vg/amst205.F97/vj09/project5.html ) , gas refrigerators work this way :\n\nsection having a series of coils containing steam. The steam is created via a gas flame. Strong liquid (ammonia mixed with water) flows over the coils and the heat from the steam causes it to boil. As a result of the boiling, the strong liquid gives off ammonia vapor which exits the generator (2). This ammonia gas leaving the generator contains a small percentage of water and is somewhat warm. The gas enters the rectifier which is an amalgam of a heat exchanger and condenser created to purify the gas by taking away the heat and water. The heat from the gas is removed by liquid flowing though the rectifier. The cooling of the gas is what removes the water vapor. The water vapor condenses and drips back into the generator (3). The ammonia gas, however, proceeds to the condenser. It is here that the ammonia vapor is reduced to a denser form - liquid. The condenser consists of a ladder of tubes parallel to one another. Water flows downward over the outside of the tubes, taking heat from the warm gas flowing through them. The temperature decreases causing the ammonia gas to change phases. At the bottom of the condenser, liquid ammonia flows out (4). This anhydrous ammonia then passes though a brine cooler. Brine is simply the salt, of any substance, dissolved in water. The ammonia chills the brine and the brine then chills the unit (5). The ammonia then passes through the evaporator where it returns to gaseous form. The ammonia then proceeds to the absorber. Here, the evaporated ammonia is dissolved into water. After the ammonia is absorbed, the liquid is now strong and the cycle can begin again. A pump draws off the strong liquid, and discharges it to the generator where the process starts over (6).
1122323
A mass flow controller is designed and calibrated to control a specific type of gas at a particular flow rate. The MFC can be given a set point (from 0 to 100%) of its full scale range. The device will then ensure the gas is flowing at the specified rate. MFCs can be either analog or digital, a digital flow controller is usually able to control more than one type of gas whereas an analog controller is limited to a single gas at a single range.\n\nAll mass flow controllers have an inlet port, an outlet port, a mass flow sensor and a proportional control valve. The MFC is fitted with a closed loop control system; this is given an input signal by the operator (or an external circuit/computer) which it compares to the value from the mass flow sensor and adjusts the proportional valve accordingly to achieve the required flow. The flow rate is specified as a percentage of its calibrated full scale
194412
go to http://en.wikipedia.org/wiki/Wankel_engine#How_it_works
1126712
Yes, we've known about electrolysis for a long time.  It's how submarines make breathable air while submerged -- they electrolyze seawater and just bubble the hydrogen overboard while releasing oxygen gas into the boat.  However, it takes a lot of energy to convert water into hydrogen and oxygen, which isn't a concern in a small space with a nuclear reactor to power everything, but it isn't a 100% efficient conversion of electrical energy into chemical potential energy.  There is a loss of energy due to heat, for instance (the electrodes heat up with current passing through them, and even the wiring that carries it there), and as with any energy system, you have to take entropy into account.  Depending on who you talk to, you can get anywhere from 50% up to 94% efficiency, but you'll always put more energy into it than you get out of burning the hydrogen later on down the line.  The reason we're still researching fuel cell and hydrogen cars comes from the mechanical efficiency of the different types of engines -- you currently still get more bang for your buck out of fuels than from an electric motor-driven car.  The energy is only reusable if burning the hydrogen generates the electricity to separate the water back into hydrogen again, in which case, you're talking about a perpetual motion system, and that's physically impossible.
153000
http://www.howstuffworks.com/fuel-cell.htm\n\nhttp://www.rmi.org/sitepages/pid537.php\n\nhttp://www.wisconsinpublicservice.com/news/cells/work.asp\n\nhttp://americanhistory.si.edu/fuelcells/basics.htm
405671
I assume you mean electrolysis?  I don't know the exact ratio of energy out to energy in, but I do know that it's not very efficient.  There will be a lot of lost energy.  What kind of H2 on demand system?  Are you trying to run an automobile?  If so, you'd need more than about 10 kilowatts of electricity.  Might as well just build an electric car if you have that much electricity to waste.
996953
Basically its a way of creating a battery by using a styrofoam cup and some other materials. To read how to make one, go to the site below.\n\nwww.exo.net/~pauld/summer_institute/summer_day15current/saltwaterbattery.html
658125
It has it's flammable state...Try to imagine it as a fuel air bomb.Thn there you will get your Idea.
394450
there are different type of pumps but basically the pump is rotated by motor. fuel flows into the pump and by pump's rotation, its outflow will have higher velocity.
303652
All right, I'm first going to explain, briefly, the structure of the cardiovascular system, and then I'll move on to how the blood transports oxygen specifically.\n\nYour heart pumps blood from the right ventricle to your lungs, where it exchanges carbon dioxide for oxygen, and then continues to your left atria. The left atria pumps the blood to the left ventricle, which pumps blood through your arteries  to your capillaries, where the oxygen is released so that cells can use it. Carbon dioxide is picked up, and the blood continues to the veins, and back to the right atria.\n\nNow, your blood contains red blood cells, which contain two important molecules, hemoglobin and myoglobin. Both have a high affinity for oxygen, so, in your lungs, where there is a high oxygen concentration, oxygen binds to each of these two molecules (until the equilibrium point is reached). The red blood cells are pumped throughout the body. \n\nIn the body, the concentration of oxygen is lower than in the surrounding atmosphere, so the amount of hemoglobin (and myoglobin) which is binding oxygen decreases until it reaches the new equilibrium point. Active tissues use oxygen quickly, forming lots of CO2, which enters the blood, and is converted to carbonic acid by red blood cells, using the enzyme carbonic anhydrase. The change in pH lowers the affinity of hemoglobin for oxygen, so more oxygen is released from other red blood cells near working tissues. The carbonic acid is released back into the blood from red blood cells, where it dissociates into a proton (H+) and a bicarbonate ion. It travels through the blood back to the lungs, where it is converted back into CO2, and diffuses across the transport surfaces of the lungs due to the concentration gradient. Then the cycle starts over.
59980
thats a pretty loaded question there...the best I can summarize is:\nglycolysis:\nglucose + 2ATP + 2NAD+ +4ADP + 2Pi= 2 pyruvate + 2 ADP + 2 NADH + 2H+ + 2ATP + 2H20\nthis takes place in the cytoplasm of the cell\n\nKreb's/TCA/Citric Acid Cycle:\n3 NADH + FADH2 + 2CO2 for each turn of the cycle\nthis happens in the mitochondria\n\nETC:\nhappens in the mitochondrial matrix but is hard to explain without diagrams...basically you get +2.5ATP for each NADH that goes through and +1.5 ATP for each FADH2 that goes through
510778
Blowing up engine? are we trying to use electrolysis to run an engine?? Try diluting the mixture with something other than oxygen. Or, better yet, just stop and let someone who knows what they are doing give it a whirl. The fact that you are here doesn't give me much faith in your chemical or engineering skills.
1162781
http://auto.howstuffworks.com/catalytic-converter2.htm