Measuring Hydrogen By Weight?

[Tremorfalcon]

From what I understand, a cars ECU calculates the air/fuel ratio by weight, not by volume.

I looked it up on wikipedia and here is the density of hydrogen.

(0 °C, 101.325 kPa)
0.08988 g/L


So, how could we use this to convert hydrogen from liters (volume) to a measurement by a weight? I'm assuming the g is grams, but I'm not sure how I'd convert that to a weight...

Weight = Mass X Acceleration due to gravity, correct?

So...1 pound = Mass X 9.8. Mass = 0.10204 kilograms or 102.04 grams. So, 102.04 grams / 0.08988g/L = 1135.2915 liters. So it would take 1135.2915 liters of Hydrogen to make 1 pound of it? Would this be correct? I havent done anything chemistry related since I was a sophomore in high school so its been a while.

[Jaxom]

It's simpler than that. If the stadard density is .09g/L, then one liter of H2 gas weighs .09 grams at atmospheric pressure and 0°C. There's a problem though...as temp. increases the gas will expand, which lowers the density. We need to know the actual temp. of the gas, as well as a temp/density curve, to find the actual weight of any given volume of H2 gas. The temp./density curve can probably be found online if you dig for it.

Then you have to factor in the oxygen content of the HHO.

[Smith03Jetta]

The problem is that you have to measure the weight in a vacuum. It is lighter than AIR so it will have a NEGATIVE weight if measured normally. If you hold a balloon full of hydrogen and stand on a scale you will weigh less.

Remember Zeppelins? Hindenburg?

[Tremorfalcon]

Alright, so I was on the right track sort of, just making it too complicated. HHO is 2/3 hydrogen so I'd have to take that into account like you said, and I figured I'd have to know the temperature of the HHO I'm producing and the density at that temperature. It'd be nice it was a linear relationship and at 64 degrees F it was half as dense as at 32 degrees F. But I hightly doubt it is, I guess I'll have to dig around for the curve. Any suggestions on how I could accureately measure the temperature of the gas? Maybe something quicker than an alcohol thermometer and letting it sit in the gas stream for a while.

[Riddler250]

I just read this thread and now I have a huge headache. WAY over my head

[Roland Jacques]

The problem is that you have to measure the weight in a vacuum. It is lighter than AIR so it will have a NEGATIVE weight if measured normally. If you hold a balloon full of hydrogen and stand on a scale you will weigh less.

Remember Zeppelins? Hindenburg?

Off topic but -- Does anybody no why the Hindenburg seemed to burned so slowly? I’m not familiar how straight H2 burns. HHO seems to burn a lot faster than the Hindenburg did. Just curious

[Painless]

Off topic but -- Does anybody no why the Hindenburg seemed to burned so slowly? I’m not familiar how straight H2 burns. HHO seems to burn a lot faster than the Hindenburg did. Just curious

From what I've read, the hydrogen went up pretty darn quick, the majority of the blaze was the material and chemicals involved in the outer skin, this burnt for the majority of the fire.

[Tremorfalcon]

I know Mythbusters did a show on it. I'll try to find it on YouTube sometime and if its not there I'll record it next time its on and post it.

[Jaxom]

.....HHO is 2/3 hydrogen so I'd have to take that into account.....


Don't forget that oxygen is heavier than hydrogen. That makes it a little more complex too.


Smith...You're right that we can't measure the actual weight of H2 in an atmoshpere, but we should be able to calculate it based on volume and denisty, if we can figure the density accurately.

[jerzhere]

I am just taking a stab at it but if you know the weight of H and O and HHO is 2/3 H and 1/3 O couldn't you just measure the output, add the H2 O weights together and determine it that way. Maybe have a flow meter that measures the output in real time... I would think this way you would not have to worry about the HHO begin hot or cold as you are monitoring the flow rate in real time.