|
|
|
|
|
|
|
|
|
 Posted: Fri Jul 01, 2005 8:56 am
Yay! Talk about the love of my life, chemistry!!!
|
 |
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Mon Jul 04, 2005 10:33 am
Chemical_Kitten Yay! Talk about the love of my life, chemistry!!! ok - what do you think about the idea of solid nitrogen as a fuel? i mean, the enthalpy difference between a nitrogen-nitrogen single bond (which is what a solid would be made up of) and a nitrogen-nitrogen tripple bond (in it's di-atomic form) is certainly one of the biggest amoungst all known chemical bonds, so an actual covailently bonded solid would store an incredible amount of energy....
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Mon Jul 04, 2005 5:22 pm
rugged Chemical_Kitten Yay! Talk about the love of my life, chemistry!!! ok - what do you think about the idea of solid nitrogen as a fuel? i mean, the enthalpy difference between a nitrogen-nitrogen single bond (which is what a solid would be made up of) and a nitrogen-nitrogen tripple bond (in it's di-atomic form) is certainly one of the biggest amoungst all known chemical bonds, so an actual covailently bonded solid would store an incredible amount of energy.... It would store a lot of energy, so much to the point that you'd only need half the amount of fuel that you would normally have in a space shuttle. I don't think they would use it in the form of a covalent bond though. I think how it would be done would be to have two rings of nitrogen, a negative and a positive ring in which the charges would hold the molecule together in an ionic bond: N5+N5-. So therefore, the nitrogen fuel would be a crystalline salt. I'm not sure as to whether they've been able to make each of the nitrogen rings yet though. I know they have N5+ in labs, but I'm not sure if N5- is. Also, do we really know how stable and safe such a fuel would be?
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Tue Jul 05, 2005 7:49 am
well heres some info of which im sure you both would have looked at, from scientific american.com
Solid Nitrogen Fuel Could Lighten Rocket Load
To escape the earth's atmosphere, rockets need a lot of fuel. So much, in fact, that much of the volume of current models is devoted to carrying it. If scientists could succeed in synthesizing more efficient propellants, it could lead to smaller spacecraft. To that end, a report published in the current issue of the journal Physical Chemistry A may help. The findings suggest that the production of a solid form of nitrogen that packs twice the energy punch of current space propellants is feasible.
Rodney J. Bartlett and his colleagues at the University of Florida ran computer simulations to investigate the properties of a new form of nitrogen known as N5+N5-. An ionic bond between a negatively charged group of five nitrogen atoms and a second group of positively charged ones holds the compound together, making it a solid crystalline salt. The positively charged half of N5+N5- has been manufactured in a lab, but N5- so far remains in the realm of conjecture.
ADVERTISEMENT (article continues below)
The Florida team posits that N5- should form a ring of five nitrogen atoms that share the negative charge equally among themselves. Their calculations further indicate that it should be stable enough to manufacture it experimentally, though the effects of the crystal's framework on the stability of the molecule remain unsolved. According to the report, N5+N5- could release a comparable amount of energy per gram as hydrazine, a liquid comprised of hydrogen and nitrogen that powers many current spacecraft. But because the density of the solid fuel is calculated to be twice that of hydrazine, only half the volume would be required to carry it, "which might allow for smaller and therefore lighter rockets." --Sarah Graham
so yeah accordig to the source, (to make this quick i only checked one), it is theretically stable "as it should spread the negitivity throughout the atoms" but is currently physically undeveloped, and the N5+N5- mixture will make the ship lighter, and therefore mpore efficent, reaping benefits the the environment, with the current rocket fuel beig highly toxic, as it forms perchlorate (CL+) as a byproduct, contaminating the local food sources. (http://www.ewg.org/issues/perchlorate/20030919/index.php)
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Tue Jul 12, 2005 1:52 pm
imagine it as an explosive, though.
yeah...... 3nodding
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Thu Jul 14, 2005 4:56 am
hehe, another 'big bang' razz imagine a firework to go off with that stuff razz
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Thu Dec 22, 2005 11:58 pm
While that sounds neat, the N5 series looks as though it is too unstable to be useful.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Tue Jan 17, 2006 11:40 pm
Woo! I get to take two medicinal chem subjects this semester. I'm so excited xd
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Sat Jan 21, 2006 6:06 pm
I've recently had a toothache: not a picnic, I'll tell you that. My sister (a dentist in training) recommended I use some baking soda to help reduce the pain a little before using some off-the-counter oral anesthetic (benzocaine... gonk )...
Baking soda is virtually made up of sodium bicarbonate (NaHCO3 (s)... That, as most of you might know is the conjugate base of carbonic acid (H2CO3).
The pKb of bicarbonate is 10.4 (the larger this value, the stronger a base is), making it a decent alkaline solution.
Cavities are caused by deminiralization caused by exposure to organic biproduct acids produced by bacteria (such as lactic and tartaric acid). I know it would help in neutralizing the acid (wich actually helped a lot mrgreen )
Does anyone know what the effects of an alkaline solution on bacteria? I'm too lazy to research anything... stare
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Sat Jan 21, 2006 6:07 pm
Chemical_Kitten Woo! I get to take two medicinal chem subjects this semester. I'm so excited xd Med chem is fun! xd I took it last year... 3nodding
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Sat Jan 21, 2006 6:12 pm
Kimyanji Chemical_Kitten Woo! I get to take two medicinal chem subjects this semester. I'm so excited xd Med chem is fun! xd I took it last year... 3nodding Coolios, I'm really looking forward to it smile
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Sun Jan 22, 2006 4:12 am
Kimyanji Does anyone know what the effects of an alkaline solution on bacteria? I'm too lazy to research anything... stare Well from my basic knowledge of Bio, all I can think of is that particular bacterias will respond to Acids and others to Bases, some can survive in one or the other. Dependent on the strand it'll depend on how it can survive.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Mon Jan 23, 2006 6:34 am
I have a Q. What is the names of the "memory metals" and "memory plastics"?
You know those metals and plastics that remember the sharp they was casted on and will return to that shape once heated, even after crushed, twisted, and stretched out of shape. I can't for the life of me remember their names, so I just call the "memory materials".
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Wed Jan 25, 2006 8:26 am
I believe they are just called memory metals for the most part, but I think they are also called "shape memory alloys." I know one alloy is Nickel-Titanium (in nearly even amounts), and you should be able to find most with a simple Google search.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Wed Jan 25, 2006 8:32 pm
rugged imagine it as an explosive, though. yeah...... 3nodding *pulls out canister and engages random person in chat* "Hey friend, here is a present, there are 10 billion dollars inside... open it!" *runs* Lol. Wouldn't that be fun? But as a fuel... meh, why bother? The space shuttle doesn't need to be lighter, it needs to be more fuel/cost efficient... and this might be more expensive but more efficient... so what then?
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Reply
