why is hydrogen prepared
Answers
One of the easiest ways to obtain hydrogen is to get it from water, H2O. This method employs electrolysis, which breaks water into hydrogen and oxygen gas.
Method 2
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Electrolysis of water is an easy way to make hydrogen gas. Wikihow/CC BY-NC-SA 3.0
byAnne Marie Helmenstine, Ph.D.
Updated November 01, 2018
It's easy to generate hydrogen gas at home or in a lab using common household materials. Here's how to make hydrogen safely.
Make Hydrogen Gas - Method 1
One of the easiest ways to obtain hydrogen is to get it from water, H2O. This method employs electrolysis, which breaks water into hydrogen and oxygen gas.
water
9-volt battery
2 paperclips
Unbend the paperclips and connect one to each terminal of the battery.
Place the other ends, not touching, into a container of water. That's it!
You'll get bubbles off both wires. The one with more bubbles is giving off pure hydrogen. The other bubbles are impure oxygen. You can test which gas is hydrogen by lighting a match or lighter over the container. The hydrogen bubbles will burn; the oxygen bubbles will not burn.
Collect the hydrogen gas by inverting a water-filled tube or jar over the wire producing the hydrogen gas. The reason you want water in the container is so you can collect hydrogen without obtaining air. Air contains 20% oxygen, which you want to keep out of the container in order to keep it from becoming dangerously flammable. For the same reason, don't collect the gas coming off both wires into the same container, since the mixture could burn explosively upon ignition. If you wish, you can collect the oxygen in the same way as the hydrogen, but be aware this gas is not very pure.
Cap or seal the container before inverting it, to avoid exposure to air. Disconnect the battery.
Make Hydrogen Gas - Method 2
There are two simple improvements you can make to improve the efficiency of hydrogen gas production. You can use graphite (carbon) in the form of pencil "lead" as electrodes and you can add a pinch of salt to the water to act as an electrolyte. The graphite makes good electrodes because it is electrically neutral and won't dissolve during the electrolysis reaction. The salt is helpful because it dissociates into ions which increase the current flow.
2 pencils
salt
cardboard
water
battery (could go as low as 1.5 V with the electrolyte)
2 paperclips or (better yet) 2 pieces of electrical wire
Prepare the pencils by removing the erase and metal caps and sharpening both ends of the pencil.
You're going to use the cardboard to support the pencils in the water. Lay the cardboard over your container of water. Insert the pencils through the cardboard so that the lead is submerged in the liquid, but not touching the bottom or side of the container.
Set the cardboard with pencils aside for a moment and add a pinch of salt to the water. You could use table salt, Epsom salts, etc.
Replace the cardboard/pencil. Attach a wire to each pencil and connect it to the terminals of the battery.
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Collect the gas as before, in a container that has been filled with water.
Make Hydrogen Gas - Method 3
You can get hydrogen gas by reacting hydrochloric acid with zinc.
Zinc + Hydrochloric Acid → Zinc Chloride + Hydrogen
Zn (s) + 2HCl (l) → ZnCl2 (l)+ H2 (g)
hydrochloric acid (muriatic acid)
zinc granules (or iron filings or strips of aluminum)
Hydrogen gas bubbles will be released as soon as the acid and zinc are mixed. Be very careful to avoid contact with the acid. Also, heat will be given off by this reaction.
Hi
Here is your answer
H2 production relies on a process called steam reforming.
This involves heating steam to 800 degrees C and combining with methane (CH4) over a catalytic material. The reactions release the Hydrogen from the methane and water molecules. The freed-up Oxygen and Carbon atoms combine to form CO2. Here’s what the reaction formula looks like:
CH4 + 2H20 + heat → CO2 + 4H2
As one might guess, this produces a lot of CO2. The molecular weight of CO2 is 44, while that of the four H2 molecules is only 8. So, not counting the source of energy to heat the steam, this means that the mass ratio of CO2 is 5.5 times greater that of the H2. If we consider the energy required to heat the steam also comes from combustion of hydrocarbons, the ratio ends up somewhere in the range of about 12:1.
One of the primary uses of hydrogen is the production of ammonia, which is used for fertilizer of most of the food that humans consume. There is, (forgive the pun), much to think about when food crops such as corn are grown to produce ethanol fuel, because the total carbon footprint also must consider the fertilizer and how it was made.
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