What is the vapor pressure of the water in the urea solution?
Q. A 650 ml aqueous solution contains 70 g of urea CO(NH2)2. The vapor pressure of pure water at 20.0 degrees C is 17.5 mm Hg. What is the vapor pressure of the water in the urea solution? (assume that the molar concentration of water in this solution is 55.5 M)
Asked by Sucipto M - Tue Jul 1 21:01:52 2008 - - 1 Answers - 0 Comments

A. Moles urea = 70 g /60.07 g/mol =1.17 Moles water = 55.5 x 0.650 L =36.1 Mole fraction water = 36.1 / 36.1 + 1.17 =0.969 p = p X = 17.5 x 0.969 = 17.0 mm Hg
Answered by Dr.A - Wed Jul 2 09:01:38 2008

How can I make urea formaldehyde resin/adhesive in a college lab?
Q. How can I make urea formaldehyde resin/adhesive in a college lab? It's what I have been given as my project, and the guide assigned to my group has blatantly said that she has no idea of how to do it. The 'net hasn't proved very helpful either. Can anyone please guide me? HELP!!! Thank you.
Asked by incognita - Wed Mar 4 09:20:53 2009 - - 1 Answers - 0 Comments

A. you need formalin 37%, and nitrogen based urea and small amount of caustic soda to make the glue which should give you 50% concentration. You will need a boiling kettle for this purpose.
Answered by S H - Fri Mar 6 23:45:17 2009

How is ammonia broken down into urea?
Q. I know that ammonia is created from the process of breaking down from protein and I know the liver converted ammonia into urea. Question is; how? If there are any specific equations, that would be great.
Asked by iEddie - Wed May 14 14:37:21 2008 - - 4 Answers - 0 Comments

A. it is broken down by deamination. demination removes the amino group of an amino acid which makes ammonia. this acid is then respired while the toxic ammonia is converted into urea through the ornithine cycle. then the kidneys remove the urea from the body the ornithine cycle is a series of reactions where toxis ammonia is combined with CO2 and a molecule of urea is assembled on the ornithine. 1 molecule of co2 and 1 of NH3 are added to the molecule of ornithine making citruline. a second molecule of NH3 is added to citruline to make arginine. arginine splits to make 1 molecule of urea and one ornithine so cycle can continue. hope this helps
Answered by MAXINE O - Tue May 20 11:24:47 2008

What is the maximum amount of urea that can be produced?
Q. Billions of pounds of urea, CO(NH2)2, are produced annually for use as a fertilizer. The balanced chemical equation for the formation of urea follows. 2NH3 + CO2 ==> CO(NH2)2 + H2O A given large scale reaction mixture has NH3 and CO2 in a 3:1 Molar Ratio. If this reaction mixture contains 27.6 kg of NH3, what is the maximum amount of urea that can be produced?
Asked by Poler - Mon Dec 21 13:48:39 2009 - - 1 Answers - 0 Comments

A. find moles using molar mass: 27.6 kg of NH3@ 1000 g / kg @ 17.031 g/mol = 1621 moles NH3 using the equation: 2NH3 + CO2 ==> CO(NH2)2 + H2O 1621 moles NH3 @ 1 mol urea / 2 mol NH3 = 810 mol urea using molar mass: 810 mol urea @ 60.06 g/mol = 48,700 grams your answers: 810 mol urea, or 48,700 grams urea
Answered by Steve O - Mon Dec 21 19:35:52 2009

Urea and ammonium sulfate are used as agricultural fertilizers.Which contains the higher weight % of nitrogen?
Q. Urea and ammonium sulfate are both used as agricultural fertilizers.Which one contains the higher weight percentage of nitrogen? Please show me the work so I can understand how you got the answer. Thank you!
Asked by jessicaperelli - Wed Jul 2 17:41:34 2008 - - 1 Answers - 0 Comments

A. Urea is (NH2)2CO with a molar mass of 60.07grams Ammonium sulfate is (NH4)2SO4...molar mass of 132.14g Urea contains 2 nitrogen atoms, that's 28g of nitrogen Ammonium sulfate also has 2 nitrogen atoms, which is also 28g of nitrogen.. Urea...28g/60.07g = 46.61% Nitrogen by mas Ammonium sulfate 28/132.14 = 21.19% Nitrogen by mass Urea is superior in % nitrogen by mass
Answered by Nuclear Sauce - Thu Jul 3 11:52:13 2008

Is there any difference between urea and all nitrogen fertilizer?
Q. Whenever I look at urea, I always see it with a high nitrogen count, but none of anything else. Does that mean urea and nitrogen are the same thing?
Asked by steve l - Wed Jun 24 16:09:36 2009 - - 4 Answers - 0 Comments

A. Urea is one of the purest - strongest form of nitrogen you can get for your lawns. Be careful in the summer months as it can burn the lawn if not watered enough or put on to heavy..
Answered by Dennis P - Wed Jun 24 17:22:43 2009

What percentage of total nitrogen waste is accounted for by urea?
Q. What is the reference range for a healthy individual ? Around how many percent of total nitrogenous waste is urea ? How much of the nitrogenous waste that we excrete is actually urea ? Not the healthy range for urea, but the percentage it contains in the total nitrogenous waste.
Asked by twinkled1990 - Wed Jan 21 04:40:23 2009 - - 1 Answers - 0 Comments

A. The three main nitrogenous waste products are Ammonia, Urea and Uric Acid. Ammonia can only be tolerated at very low concentrations. Urea is produced in the vertebrate liver by a metabolic cycle that combines ammonia with carbon dioxide. Urea has a low toxicity, about 100,000 times less than that of ammonia. This allowes animals to transport and store urea safely at high concentrations. Urea excretion requires much less water, becausemuch less water is lost when a given quantity of nitrogen is exvreted in a concentrates solution of urea rather than a dilute solution of ammonia. I have tried looking for it online but didn't find anything more. Since you asked for reference range i found that out. I still try looking for you answer… [cont.]
Answered by Yahoo Answers - Wed Jan 21 06:46:50 2009

How does the amount of protien in the diet, influence urea excretion?
Q. Low protien diet - how much urea produced and why? Normal protien diet - how much urea produced and why? High protien diet - how much urea produced and why? :) thank you
Asked by cinnamonstar123 - Wed Apr 30 14:55:00 2008 - - 2 Answers - 0 Comments

A. The more protein in the diet, the more protein that is broken down. This means the amine (NH2) group of the protein is detached (deamination) and broken down to produce urea in the liver and then sent to the kidney.
Answered by jaymerr2001 - Wed Apr 30 15:07:32 2008

What microcontroller(8051 family) based projects can be done for a chemical plant which manufactures UREA?
Q. we want to create a project for a urea based plant with a microcontroller.we want to know what project can be done on this plants.
Asked by dude logic - Wed Aug 19 07:24:16 2009 - - 1 Answers - 0 Comments

A. The 8051 lends itself to simple real-time data acquisition or control tasks. I assume this is a one-man project, so you won't be taking over the task of automating the entire process. I would suggest to work with the Quality department of the plant. Quality engineers are always interested in capturing data that is not currently available. So you could make a system that automatically takes measurements at one point of the chemical process and sheds some light on what can be improved in the process.
Answered by Frank L - Sat Aug 22 13:42:38 2009

Why are urea and uric acid reabsorbed into the body?
Q. After they are absorbed into the kidney, why is it that a small amount is then re absorbed into the body again? what purpose does urea and uric acid serve in the body?
Asked by calculator factory - Wed Apr 1 04:51:49 2009 - - 1 Answers - 3 Comments

A. They are not reabsorbed.
Answered by Ishan26 - Sat Apr 4 21:35:58 2009

how to calculate the value of blood urea nitrogen from the value of blood urea?
Q. imagine your blood urea value is x.then what is your blood urea nitrogen value?
Asked by vinu - Wed Oct 24 02:45:07 2007 - - 1 Answers - 0 Comments

A. Maybe you can use the molar mass or molecular weight this way: molar mass of N = 14 molar mass of urea = 60.07 urea molecular formula: CO(NH2)2 that is, one mol of urea contains 2x14 nitrogen molar masses, so take your known value and multiply it this way: BloodUreaValue x 28/60.07 = blood urea nitrogen value
Answered by Joecat73 - Wed Oct 24 19:21:42 2007

How does the addition of Urea affect an enzyme-controlled reaction?
Q. Urea breaks hydrogen bonds.
Asked by Larentis - Sun Nov 30 07:02:49 2008 - - 1 Answers - 0 Comments

A. The urea will disrupt the precise 3 - D structure of the enzyme and as a result loss of activity will follow.
Answered by Peter S - Sun Nov 30 07:21:06 2008

What is the mole fraction of urea in a solution that contains 2.2 mol of urea and 5.2 mol of water?
Q. What is the mole fraction of urea in a solution that contains 2.2 mol of urea and 5.2 mol of water? A. 0.40 B. 0.30 C. 0.77 D. 0.50 E. 0.70
Asked by China - Sun Jun 1 20:19:05 2008 - - 1 Answers - 0 Comments

What is the pathway of urea from the renal artery to the collecting ducts?
Q. If you can, I'd prefer to see a website where I can verify your answer.
Asked by HalfBloodPrincess - Tue Jan 26 20:58:53 2010 - - 1 Answers - 0 Comments

A. it goes into the glomerulus which is the head of the nephron, and it goes through all of those channels including absorbing certain nutrients back into the body.
Answered by mtwaites - Tue Jan 26 21:17:03 2010

How do you find the molecular mass of Urea?
Q. Urea CH4N2O I missed our class covering this chapter and my friend told me the Molecular mass was the Molar mass of each substance in grams, and instead of writting grams you use amu. Is that right? C=12.01g H*4=4.032g N*2=28.02g O=16.00g So the molecular mass of Urea is 60.062 amu? Thanks for help
Asked by simply_college - Sun Apr 20 14:05:24 2008 - - 1 Answers - 0 Comments

A. Thats right! and to be sure, you can look it up, and your answer should be about 60.07g/mol (or amu). good job.
Answered by tifforific - Sun Apr 20 14:09:40 2008

What is the point of urea recycling? As far as I can see it serves no purpose....?
Q. I've been studying the kidneys and urea recycling came up. I understand what happens and how the urea is recycled but I don't see the point in it. Surely we want to excrete all of the urea instead of dragging it back into the interstital fluid and then into the ascending limb of the loop of henle etc
Asked by Moi? - Sun Dec 7 16:30:59 2008 - - 1 Answers - 0 Comments

A. Urea recycling serves a very important purpose! Water reabsorption from filtrate in the collecting duct and the Loop of Henle is due to increased solute concentration in the renal medulla. One of those solutes is, of course, sodium chloride, but the other one is urea! Only a portion of the urea in the filtrate leaves the collecting duct. This additional urea in the interstitial fluid helps "pull out" more water from the filtrate by osmosis. The urea is then returned to the ascending limb of the Loop of Henle - after its job is done - precisely because it now can continue its journey towards excretion. This two solute system enables us to produce a concentrated urine. If we were not able to do this, we would have to drink over a hundred… [cont.]
Answered by Nickname (exactly 32 characters) - Sun Dec 7 17:01:43 2008

How does urea inhibit enzymes?
Q. I've read that urea inhibits amylase by disrupting the noncovalent bonds. Is it active site directed (competetive) or non active site directed? And reversible or irreversible?
Asked by olivegreen - Wed Jan 10 06:38:03 2007 - - 1 Answers - 0 Comments

A. Urea is a very strong denaturing reagent because of its highly polar structure (H2N-CO-NH2, with a double bond between C and O). The strong localized charges will interact with the aminoacid structure of any protein and enzyme (especially the secondary chains) and disrupt their function. So it is not directed to the active site. Theoretically, the process is reversible, but you need to progressively remove UREA from your solution, as if you remove it completely the denatured proteins will precipitate as insoluble material. This is what you should do: resuspend your samples in UREA (generally between 6 and 8M, but less could also be enough) to solubilize and inactivate the enzyme. Then dialyse your protein suspension against the same… [cont.]
Answered by lovely green eyes - Wed Jan 10 07:28:53 2007

What aspect of the solubility of urea is essential for the function of the synapsid kidney?
Q. I cannot figure this one out... The answer is something like: Its (low/high) solubility (allows/prevents) (low/high) concentrations from being excreted in (solid/liquid) urine
Asked by Chris F - Sun Apr 5 21:06:56 2009 - - 1 Answers - 0 Comments

A. Its high solubility allows high concentrations to be excreted in liquid urine. Urea is highly soluble so it allows high concentrations of solutes to be excreted in liquid urine, which is what you want since solid urine would be unable to pass through the rest of the system.
Answered by The Major - Sun Apr 5 22:58:18 2009

Which blood vessel contains the lowest concentration of urea?
Q. I have a huge exam tomorrow and that is the only question on my study guide that I can not seem to find the answer to...Please help!
Asked by AwatemonoSan - Mon Nov 23 23:44:14 2009 - - 1 Answers - 0 Comments

A. I would say it's the renal veins. The kidneys are what removes urea from the bloodstream, so it would make sense that the blood vessel immediately "downstream" of the kidneys would have the lowest concentration of urea in the body.
Answered by Spaghetti Cat - Tue Nov 24 00:04:35 2009

I am growing aquatic plants in urea. They died 2 weeks in. So how do i rite results if hypothesis failed?
Q. I am meant to include graphs and tables in my results. I know that if a hypothesis failed there are still things to rite about in the discussion. But my experiment still has to go for another 2 weeks (subject requirement) and all I will have left in the end is mushy plants that will disintegrate at my touch. I was meant to be recording their growth and now its more like they are shrinking to nothing!!!
Asked by J J - Sat Mar 29 23:55:16 2008 - - 1 Answers - 0 Comments

A. All experiments work. If they don't work the way that you expected them to do, you may have to modify your procedure to ask the question that you wanted to ask. Perhaps the concentration of urea was too strong for the plants to tolerate. Perhaps the bacterial concentration was too high. All I can suggest is starting over. Don't throw out the original experiment, though. Explain the results and why you changed the procedure. If you need more time for a class assignment, explain the problem to the teacher and ask for another couple of weeks.
Answered by oikos - Sun Mar 30 10:46:59 2008