[Marklar37]

What common Household things have DC currents?  (Radios ect.)

P.S. i am trying to make a hoffman apparatus and i need power

[Alpha-Omega]

AC and DC stand for ’alternating current’ and ’direct current,’ respectively. Current means the flow of electrical charge from place to place. DC keeps flowing one way. If It flows a long time, that means that current flows around in a loop, always the same way. A battery provides a steady push, so battery circuits (like in flashlights) have DC.

Alternating current (AC) is what you get from most wall outlets. It flows back and forth, switching directions. Most motors are designed to run off ac. Many electronic devices need dc somewhere inside, so they have devices called rectifiers that convert ac to dc.

DC is useful for appliances that run on a steady current itself. Just about all electronic devices use DC. For example, your TV plugs into an AC wall outlet, but the first thing that the circuitry in the TV does is convert this into DC, which is what the rest of the circuitry needs.

Alternating current or AC is electric current that reverses direction of flow at regular intervals.  Most modern appliances that are plugged in use this type of current.  Electricity supplied by the electric company also use AC.  Direct current or DC is electric current that flows in 1 direction. 
Appliances that run on batteries use direct current.

[Marklar37]

so what would be a good appliance to use for my project?

[Arkcon]

If you want to capture a test tube's worth of oxygen and hydrogen, a lantern battery and some bare wire are all you need.  If you need mega-watts to put the energy giants out of business, you should start with an electrical engineering degree, and work on a way to acquire venture capital.  If you're somewhere in the middle, you can look up rectifier on google.  Whether you should is up for grabs at this point.

[ARGOS++]

Dear Marklar37;

It depends on how many liters of Hydrogen and Oxygen you would like to produce.

If it’s only some Liters for a few Experiments, then best/cheapest would be to use Batteries of Type “D” (see on Wiki.) which you can “staple” (in serial connection) to get enough voltage for the electrolysis.

It will be wise to use an adjustable Power Resistor to limit the Current to a certain secure level!

For large amounts a small adjustable direct current power source converter may be indicated.
(But that’s not so cheap anymore.)

For Voltage, Security, and other information read at least:"Electrolysis of Water”


Good Luck!
                    ARGOS⁺⁺

[Marklar37]

does the amount of water matter?

[ARGOS++]

Dear Marklar37;

Not at all! – except how many liters of Gas you can produce before you have to reload!

But take anyway care, and don’t forget the electrolyte and the Resistor!

Good Luck!
                    ARGOS⁺⁺

[Marklar37]

. shout        electrolyte and the Resistor...   i dont remeber y i need those.  hydrogen goes to the negative end and oxygen goes to the positive end   right?
what more is there?

[ARGOS++]

Dear Marklar37;

Have you read the reference I have given you?

In the electrical sense the Hoffman apparatus acts like a Resistor.
If you add a small amount of Sulphuric Acid you can lower this internal Resistor and get a higher rate of generation.
But on the other side if you don’t control the current with a external adjustable Resistor you can come too fast in generation and heat the apparatus  till it may break, and finally get an explosion.
Maybe you have a little to read how Voltage, Current, and Resistors are related.

Good Luck!
                    ARGOS⁺⁺

[Marklar37]

sry i didnt know that was a link lol        thank you

[Marklar37]

so when i failed once again to remember that water alone doesn't conduct electritity, I added some salt to it  and it seems to work except that only the hydrogen is "bubling"
the oxygen only seems to cerode.

P.S.  sry my spelling is bad

[Arkcon]

so when i failed once again to remember that water alone doesn't conduct electritity, I added some salt to it  and it seems to work except that only the hydrogen is "bubling"
the oxygen only seems to cerode.

P.S.  sry my spelling is bad

Ah.  If you've used table salt, you're getting hydrogen alright, but you're making chlorine, instead of oxygen at the anode.  The chlorine is likely redissolving in the resulting NaOH, to make sodium hypochlorite, so you're salt water is becoming nasty quickly.

Like ARGOS++'s link said, sodium sulfate would be a better choice, if you can't use sulfuric acid.

[Marklar37]

i dont have any of these chemicals,   is there anything else besides salt i can use?

[ARGOS++]

Dear Marklar37;

Are you able to find some “Baking Soda” or “Baking Powder”?
If it is for the main part made of “Sodium Bicarbonate” it should work, but you will have to discard first few Liters of generated Gas, because CO2 and other gas.
It should work as a “Sodium Hydroxide” replacement.

As in most case “Baking Soda” is not a pure product I can not take any guarantee for a real success.
But remember you need only a small amount of this electrolyte.

Good Luck!
                    ARGOS⁺⁺

[Marklar37]

what about viniger?