NH3/CH4

4 comments

NSS Guru Join Date: Aug 2007 Posts: 885 Good Answers: 9	NH3/CH4 03/14/2024 10:23 AM
	What is the density difference between these two? I know NH₃ can be used as a lifting gas in a balloon. CH₄? What would it's lifting power be like compared to NH₃ or H₂? say 1 cu meter of CH₄ at sea level can lift how much? Joe
	Register to Reply

Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

These comments received enough positive ratings to make them "good answers".

PWSlack Guru Join Date: Jan 2007 Location: In the bothy, 7 chains down the line from Dodman's Lane level crossing, in the nation formerly known as Great Britain. Kettle's on. Posts: 31729 Good Answers: 834	#1 Re: NH3/CH4 03/14/2024 10:43 AM
	Temperatures and pressures are all: Look for a pressure-density-temperature relationship for each material. Of those three, at ambient temperature at sea level, <...H2...> is the best for a <...balloon...>. As the temperature drops, with altitude, the first one to liquefy is <...NH3...>, making it unsuitable for use at high altitudes. <...CH4...> is a better lifter at ambient temperature at sea level than <...NH3...>. <...H2...> outperforms both of the above and is easy to manufacture by electrolysis. The potential for <...NH3...> and <...CH4...> to annoy environmentalists at ambient temperature and sea level vastly exceeds that of <...H2...>, which leaves the atmosphere when it leaks or the <...balloon...> bursts. (all retrieved from a simple internet search - highly recommended) __________________ "Did you get my e-mail?" - "The biggest problem in communication is the illusion that it has taken place" - George Bernard Shaw, 1856
	Register to Reply Good Answer (Score 2)

NSS Guru Join Date: Aug 2007 Posts: 885 Good Answers: 9	#2 In reply to #1 Re: NH3/CH4 03/14/2024 10:46 AM
	When/if would CH4 liquify?
	Register to Reply

PWSlack Guru Join Date: Jan 2007 Location: In the bothy, 7 chains down the line from Dodman's Lane level crossing, in the nation formerly known as Great Britain. Kettle's on. Posts: 31729 Good Answers: 834	#3 In reply to #2 Re: NH3/CH4 03/14/2024 12:10 PM
	<sigh> These things just need looking up, that's all. Invitation declined. <unsubscribes> __________________ "Did you get my e-mail?" - "The biggest problem in communication is the illusion that it has taken place" - George Bernard Shaw, 1856
	Register to Reply

Rixter Guru Join Date: Apr 2010 Location: About 4000 miles from the center of the earth (+/-100 mi) Posts: 9658 Good Answers: 1102	#4 Re: NH3/CH4 03/14/2024 1:37 PM
	At standard temperature and pressure a mole of gas fills 22.4 liters. So you can assume the density is proportional to molecular weight. (A mole is the atomic weight x 1g) H₂ - molecular weight = 2g NH₃ - molecular weight = 14 +3 = 17g CH₄ - molecular weight = 12 + 4 = 16g N₂ - molecular weight = 2 * 14 = 28g O₂ - molecular weight = 2 * 16 = 32g Argon - molecular weight = 40g Air = 78% N₂ + 21% O₂ + 1% Ar = .7828 + .2132 + .0140 = 29g lifting power H₂ = 29 - 2 = 27g lifting power He = 29 - 4 = 25g 1 cubic meter = 1000 liters or 1000/22.4 moles of gas weight of cubic meter H2 = 1000/22.4 2 = 89 grams weight of cubic meter of Air = 1000/22.4 * 29 = 1295 grams A cubic meter of Hydrogen can lift 1295 - 89 or 1206 grams lifting power NH₃ = 29 - 17 = 12g lifting power CH₄ = 29 - 16 = 13 So lifting power of Hydrogen and Helium are approximately the same. Lifting power of ammonia and methane are about the same and approximately half of lifting power of hydrogen or helium.
	Register to Reply Good Answer (Score 5)

Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.