Number of results: 91,913
chemistry
http://www.biochem.northwestern.edu/holmgren/Glossary/Definitions/Def-S/saturated_solution.html
Monday, August 4, 2008 at 3:40pm by DrBob222
biology
http://www.biochem.uwo.ca/meds/medna2/NAchem.html Notice the links at the bottome of the page, they lead to the other answers.
Monday, December 31, 2007 at 5:08pm by bobpursley
biochem
thank you so much. I just recently went back to school and havent had chemistry in more than 4 years and math has been even longer. I really appreciate the help :)
Saturday, September 10, 2011 at 6:40pm by amy
science(chem)
See if this will help you. http://www.science.smith.edu/departments/Biochem/Biochem_353/Buffer_Prep.html#top There is a better site but I can't find it now. Its done by Haverford College (UK).
Sunday, September 21, 2008 at 11:28pm by DrBob222
science
http://www.biochem.northwestern.edu/holmgren/Glossary/Definitions/Def-R/recessive_allele.html
Tuesday, February 16, 2010 at 8:44pm by Ms. Sue
Biochem
ggfgvgf
Monday, September 14, 2009 at 9:54am by Anonymous
Biochem
what is the pKa?
Thursday, May 6, 2010 at 3:57pm by Dr. Nick
Biochem
What salt? what acid? what's the pH.
Monday, November 19, 2012 at 8:17pm by DrBob222
Biochem
See your post above.
Sunday, September 30, 2012 at 9:45pm by DrBob222
biochem
Why concentration of salt is 0,05?
Tuesday, March 27, 2012 at 2:22pm by Anonymous
BioChem
H2PO4^- + OH^- ==> HPO4^-
Friday, March 23, 2012 at 10:17am by DrBob222
BioChem
What is the pH of hydroiodic acid (HI)?
Thursday, September 1, 2011 at 10:20pm by Max
Biochem
The conc is 6.0M HCL
Monday, September 13, 2010 at 10:50pm by Jeff
BIOCHEM
calculate the pH of 0.0076M KOH
Friday, September 7, 2007 at 4:08am by CHEM
BioChem
Wouldn't that be 0.4mg/mL x (1.00/0.25) = ?
Monday, October 31, 2011 at 10:38pm by DrBob222
biochem help needed
"College" is not the subject. Please be more specific.
Saturday, October 16, 2010 at 7:23pm by drwls
biochem
What is the structure and net charges of Aspartate, Lysine and Alanine at pH 7.5
Saturday, January 28, 2012 at 10:04pm by age
Biochem again add on
I have the pka from previous problems 4.75
Thursday, September 11, 2008 at 12:44am by bugbabe623
Enzyme Kinetics-Km values
http://www.worthington-biochem.com/introbiochem/substrateconc.html If the Michaelis factor is lower, more of the enzymes have bound in to a substrate-enzyme complex, resulting in a higher velocity of reaction production. The max km of course is at 1/2 the max velocity (...
Saturday, January 31, 2009 at 2:08pm by bobpursley
Bio/Biochem/Chem
Use the Nernst equation: E=(RT/zF)ln([K+]o/[K+]i)
Thursday, February 7, 2013 at 1:28pm by Devron
Biochem
But then if they ask us to predict the pH of this solution, using the Handerson-Haselbach equation...?
Wednesday, September 10, 2008 at 11:29pm by Pham
REPOST biochem
i don't understand this why can carboxyl and phosphate groups act as acids? as in, what makes an acid?
Thursday, October 18, 2007 at 9:45pm by J
biochem
ph is 4.6, pKa is 4.76 in a .15M buffer solution, what are the concentrations of acid and base?
Monday, September 17, 2012 at 7:39pm by Lola
BioChem
Greater than (fill in your highest concn) OR you can extrapolate the graph in some circumstances and read it.
Monday, October 31, 2011 at 10:33pm by DrBob222
Biochem
You need to read your posts to make sure they are ok. This post omits the concn HCl.
Monday, September 13, 2010 at 10:50pm by DrBob222
biology terms
http://www.worthington-biochem.com/introbiochem/substrateconc.html http://dictionary.reference.com/
Monday, October 6, 2008 at 5:57pm by Ms. Sue
BIOCHEM
what are the problems created by using molecular oxygen as a recipient of the electrons from the oxidation of carbon compounds.
Monday, March 14, 2011 at 6:32pm by DAN
biochem
I believe human and animal cells do not have cell walls but get a second opinion. I'm no biochemist.
Monday, September 28, 2009 at 7:05pm by DrBob222
Biochem
Frankly, I recommend flash cards. They are easy to make, efficient, and have a proven record.
Wednesday, September 12, 2007 at 2:50pm by bobpursley
college majors
Biochemistry, or premed, or medical science, or chemistry, or biology, or even medical technology. You need a high MCAT, and getting biochem, premed, or medical science bachelors is an excellent prep for the MCAT.
Friday, September 4, 2009 at 9:45pm by bobpursley
Chemistry (or Physio/Biochem)
H2O + CO2 <==> H2CO3 <==> H^+ + HCO3^- So if we restrict the breathing, CO2 rises, and Le Chatelier's Principle says that will force the reaction to the right; therefore, my best guess is that the blood pH will decrease (become more acid).
Sunday, March 14, 2010 at 9:14pm by DrBob222
biochem
N, O, and F are the negative ions that make hydrogen bonds. Other atoms are not electronegative enough to do that. Which pair does NOT have N, O, F?
Sunday, January 27, 2013 at 12:36pm by DrBob222
biochem
If you were to place a bacteria that could form spores in a stressful environment, what would the cell morphology look like?
Tuesday, October 20, 2009 at 7:56pm by chrissy
biochem
can someone help me write a balanced 1/2 rxn for the oxidation of glyceraldehyde-3-phosphate to glycerate-1,3-bisphosphate? I confused on where to put the electrons and how many are needed
Saturday, December 3, 2011 at 3:19pm by amy
BIOCHEM
pOH= -log(.0076) and pH= 14 -pOH
Friday, September 7, 2007 at 4:08am by bobpursley
biochem
I am confused on the dillution of the MgCl2 do I have to divide by 95 because it is only 95% pure?
Sunday, March 10, 2013 at 3:10pm by She
biochem
I had problems posting, which required that I do it in two parts, which required some time.
Saturday, February 9, 2013 at 6:12pm by Devron
Biochem
10ml of HCl acid titrate with 9.9ml of NaOH. What is the mass in grams of HCl?
Tuesday, August 3, 2010 at 5:04pm by Amrik
Biochem
Can someone please help me find, or know of any molecules that are at least 20 bases (carbons, nitrogens..) long and have 3 hybrids (sp, sp2, dsp)
Thursday, December 28, 2006 at 10:08pm by Kara
BioChem
If you run an unknown sample and it is darker than your highest standard on your standard curve, what do you report as the concentration?
Monday, October 31, 2011 at 10:33pm by Dreamland11
Biochem
How many silver coins (weighing 26g each) would it take to provide 5 moles of silver(Ag).
Tuesday, September 27, 2011 at 1:00pm by Anonymous
Biochem
I have to memorize the 20 amino acids and some nucleotides...do you know where I can find some mnemonic tips for this???
Wednesday, September 12, 2007 at 2:50pm by Julie
intro to biology
These sites should give you some help with that. http://www.mun.ca/biochem/courses/3107/Topics/Euk_prot_synth.html http://en.wikipedia.org/wiki/Cell_(biology)#Protein_synthesis
Friday, July 17, 2009 at 4:49pm by GuruBlue
Philosophy
Yea... lemme drop all work I currently have for finals to write your philosophy paper -_-
Saturday, January 29, 2011 at 12:07am by Biochem-Doc
BioChem
Write the chemical equation for the reaction that occurs when you add NaOH solution to NaH2PO4/Na2HPO4 buffer solution
Friday, March 23, 2012 at 10:17am by Megan
Biochem
1 mole Ag = 107.87 so 5 moles is 5*that = approximately 540 g. So how many coins at 26g each will make 540 grams?
Tuesday, September 27, 2011 at 1:00pm by DrBob222
biochem
I have 0.500ml of 3M ethanol and then I take 0.250ml of it and put it to 0.250ml of 0.06M phosphate buffer, what is the final concentration?
Tuesday, March 27, 2012 at 10:01pm by trouble
Biochem
What concentration of competitive inhibitor is required to yield 75% inhibition at a substrate concentration of 1.5x10-3 if Km=2.9x10-4 and Ki=2x10-5?
Sunday, April 17, 2011 at 2:36pm by Bradley
biochem
Many of today’s antibacterial drugs work by interfering with the growth of cell walls, why do these drugs tend to have little toxic effect on humans?
Monday, September 28, 2009 at 7:05pm by chrissy
Biochem
The pK of acetic acid is 4.76. Which statement is true at pH 5.0? [A^-] = [HA] [A^-] < [HA] [A^-] > [HA]
Sunday, August 28, 2011 at 4:59pm by Zack
biochem
I think that is where I keep getting stuck, with the basic math. I have 0.631 = .180x/10-0.1x and dont know where to go from there. Math was a long time ago for me :)
Saturday, September 10, 2011 at 6:40pm by amy
Biochem
What is the pH and pOH a solution that was made by adding 400 mL of water to 350 mL of 5.0 x 10^-3 M NaOH solution?
Friday, September 2, 2011 at 1:02am by Max
Biochem
HCl + NaOH ==> NaCl + H2O You don't have enough information to work a problem. You must know the M of either the HCl or the NaOH.
Tuesday, August 3, 2010 at 5:04pm by DrBob222
Biochem
This is just a dilution problem. 5E-3M NaOH x [(350)/(350+400)] OR use the dilution formula of mL1 x M1 = mL2 x M2
Friday, September 2, 2011 at 1:02am by DrBob222
biochemstry
Look at biochem testbook. "Acetal CoA is a cental character in the cellular metabolism... [through which] all the energy sources (fats, proteins, and carbohydrates) are interconvertible". Acetyl CoA is the correct answer.
Tuesday, September 1, 2009 at 10:26am by Mark
Biochem
When trying to purify a protein using column chromatography, what happens to the mass of the protein eluted from the column if you accidentally run it dry? Would it be more or less? Thanks.
Monday, October 18, 2010 at 11:35pm by Nancy
science
Thank you for using the Jiskha Homework Help Forum. First of all, do you mean "affect" or "effect?" Please see t5he following: 1. http://en.wikipedia.org/wiki/Enzyme_inhibitor 2. http://www.worthington-biochem.com/introbiochem/inhibitors.html 3. (animation...
Monday, September 15, 2008 at 4:49pm by SraJMcGin
biochem
Two equations. pH = pKa + log(base)/(acid) or 4.6 = 4.76 + log b/a b + a = 0.15 Solve the two equations simultaneously for b and a.
Monday, September 17, 2012 at 7:39pm by DrBob222
biochem
When making Aspirin, I know that sulfuric acid is used as a catalyst. But i was wondering 1.) if the reaction would happen without the cataylst and 2.) can other substances be used as a cataylst in this reaction?
Sunday, January 24, 2010 at 2:36pm by chrissy
Biochem
My best guess is that it would be less. If the column runs dry the protein sticks to the stationary phase, and you have no assurance that (a)the protein will re-enter the mobile phase in its entirety, and (b) that no degradation of the protein will occur.
Monday, October 18, 2010 at 11:35pm by DrBob222
Biochem
I must tell you that I'm not a biochemist and I don't know the equilibrium reactions you need; however, two equations will solve your problem. The first one is the Henderson-Hasslebalch equation of pH = pKa + log [(base)/(acid)] and second the equilibrium constant ...
Wednesday, January 30, 2008 at 6:46pm by DrBob222
biochem
Yes, the Henderson-Hasselbalch equation is what you use. If x = mL sodium benzoate (base) then 100-x = mL benzoic acid(acid). 4.00 = 4.20 + log(0.18x)/[(100-x)*0.1] and solve for x
Saturday, September 10, 2011 at 6:40pm by DrBob222
Biochem
calculate the volumes of 0.10 M acetic acid and 0.20 M sodium acetate that are needed to prepare 48-mL buffer solution with pH = 3.70. Ka for acetic acid is 1.75 x 10-5
Friday, April 22, 2011 at 6:01am by Iris
Biochem again
Thanks for answering the first one :) Here is another Calculate the amount of sodium acetate and acetic acid necessary to make 100mL of a 0.500 M acetate buffer that is pH 5.2. I believe I have the answer but I want to make sure I did the work correctly.
Thursday, September 11, 2008 at 12:44am by bugbabe623
Biochem
A buffer solution is prepared by mixing 200 mL of 0.2 M salt solution and 400 mL of a 0.2 M acid solution. What is the concentration of the resulting buffer? ~what is the pKa?
Monday, November 19, 2012 at 8:17pm by Dr. Nick
biochem lab
any help with any of these questions is appreciated. Why was lysozyme pipetted with the Drummond micropipetter? Why can we crystallize lysozyme at room temperature when most proteins require 4 degrees celcius? Why can lysozyme experiments be set up without preservatives needed...
Wednesday, April 30, 2008 at 1:53am by stew
biochem
If I am given a solid chemical form of both the acid and the base, how do I determine how many grams of each I need to make 1L of a 25mM Tris-HCl buffer with acid concentration of 18.94mM, and base concentration of 6.06mM?
Thursday, February 17, 2011 at 1:35pm by Jenny
biochem
Exactly 100 bacteria with a generation time of 30 min are introduced into fresh sterile broth at 8am and maintained at an optimum incubation temperature throughout the day. How many bacterian are present at 3pm? How many generation will take place by 5pm the same day?
Thursday, September 24, 2009 at 5:07pm by chrissy
Biochem
Describe the one dehydration reaction in glycolysis. Include reactants, products, enzyme, and which step it is. I know that it is step 6 and I believe that the reaction uses glyceraldehyde-3-phosphate dehydrogenase to convert glyceraldehyde-3-phosphate into 1,3-...
Monday, April 6, 2009 at 11:49pm by Jaime
science
Thank you for using the Jiskha Homework Help Forum. Here are some sites for you: 1, http://www.elmhurst.edu/~chm/vchembook/580DNA.html 2. http://www.biochem.uwo.ca/meds/medna/NAchem.html 3. http://www.diffen.com/difference/Dna_vs_Rna 4. http://www.newton.dep.anl.gov/askasci/...
Wednesday, April 9, 2008 at 6:50pm by SraJMcGin
Biochem
Calculate the amount of Tris(hydroxlmethyl)aminomethane(Tris) necessary to make 100mL of a 0.100 M Tris buffer that is equimolar in Tris-base (MW=121.1 g/mol) and Tris-HCL (MW= 157.6g/mol)
Wednesday, September 10, 2008 at 11:29pm by bugbabe623
Biochem
HEPES, is a commonly used component of physiological buffers. The PKa of the protonated amino group of HEPES is 7.55 at 25C. Describe the preparation of 1.00L of 0.100M HEPES buffer, pH 8.00, from the sodium salt of the basic form of HEPES (MW 260.3), .0M HCL and deionized water
Monday, September 13, 2010 at 10:50pm by Angel
science(chem)
(proceeds to slam head on desk) I have all my books but if I'm not incorrect, this isn't going to help in the, "real world." =/ I knew I was supposed to actually remember everything. The thing is that you remember it during the sememster and then it starts ...
Saturday, July 26, 2008 at 10:02pm by ~christina~
biochem
Yes, if you divide the right number by the right number. :-) Calculate the grams MgCl2 you need, then divide that number by 0.95 to find the final grams to use.
Sunday, March 10, 2013 at 3:10pm by DrBob222
biochem
of what? the ethanol? The final concn of the ethanol, assuming volumes are additive, is 3M x [0.250 mL/(0.250+0.250)] = 1.5M right? (Note: ethanol and water volumes are not additive. Approximately 4% error).
Tuesday, March 27, 2012 at 10:01pm by DrBob222
reading
My youngest daughter was an auditory learner, often she would read her biochem text aloud into a recorder, then play it back to herself. But she did develope strategies that worked with reading, like taking text notes, using flash cards, and using a reading mask in texts that...
Thursday, January 15, 2009 at 9:11pm by bobpursley
Biochem
It isn't clear from your post if the standard was diluted in a manner similar to that of the sample. I will assume it was; if not you will need to make a adjustment for the dilution. If the sample is 4.5 mM and gave A = 0.5, it must be a higher concn than the standard at A...
Sunday, September 30, 2012 at 9:50pm by DrBob222
Biochem
The theory of ATP synthesis by the ATP synthesis apparatus is called the _______ theory. I have no idea. Can some please help? Go to www.google.com and type in "ATP synthesis" without the parentheses. I think you will find your answer about four or five references ...
Thursday, July 20, 2006 at 5:05pm by shamaev
biochem
I need to create a 100ml buffer with a pH of 4.00 using 0.100M Benzoic acid (pKa = 4.20)and 0.180M sodium benzoate. What volume of each material do I need to make this buffer? I think I need to use pH=pKa + log(A/HA)but am not sure if that is correct. Any help would be ...
Saturday, September 10, 2011 at 6:40pm by amy
science
Thank you for using the Jiskha Homework Help Forum. I just answered this one for Jonathan: * science - SraJMcGin, Wednesday, April 9, 2008 at 8:17pm Thank you for using the Jiskha Homework Help Forum. Here are some sites for you: 1, http://www.elmhurst.edu/~chm/vchembook/...
Wednesday, April 9, 2008 at 4:51pm by SraJMcGin
BioChem
If you want to determine the actual salicylate concentration for a sample that gives you a darker color than the highest standard, you would need to make a dilution of it. If you dilute it by mixing .25 mL of sample with .75 mL of water and then find that this mixture has a ...
Monday, October 31, 2011 at 10:38pm by Dreamland11
biochem
Which of the following pairs of compounds would NOT make a hydrogen bond with each other? CH3 and H20 H20 and HF NH4 and HF H2O and CH3COOH all of the following would make hydrogen bonds
Sunday, January 27, 2013 at 12:36pm by Jen
science biochem- please help!!!!
I don't know where to start with it? A tube is set up for radioimmunoassay containing antibody with a capacity for binding 1ug antigen. Both labelled (50,000 counts per ug) and unlabelled antigen are added to the tube. Work out a formula to calculate the amounts of counts ...
Sunday, February 27, 2011 at 5:51pm by Isabel
biology
Since this is not my area of expertise, I searched Google under the key words "enzyme concentration activity" to get these possible sources: http://www.chemsoc.org/networks/learnnet/cfb/enzymes.htm http://www.worthington-biochem.com/introbiochem/enzymeConc.html http...
Sunday, March 2, 2008 at 12:37am by PsyDAG
biochem.
http://wiki.answers.com/Q/What_does_hypertonic_and_hypotonic_and_isotonic_mean
Tuesday, September 23, 2008 at 9:29pm by DrBob222
biochem
It would have a clear spot in the middle of the cell if you try a Gram stain, but if you use a spore stain, it would have a green spore inside of the red cell. P.S. You shouldn't wait until the night before your lab manual is due before you decide to do it.
Tuesday, October 20, 2009 at 7:56pm by Bob
Chemistry (or Physio/Biochem)
Asthma affects about seven percent of the population. During an asthma attack smooth muscle cells in the bronchi constrict, the airways become inflamed and swollen, and breathing becomes difficult. What effect might an asthma attack have on blood pH? A. pH goes down B. pH goes...
Sunday, March 14, 2010 at 9:14pm by Trixie
Bio/Biochem/Chem
Okay, I am assuming that this is at 25º C R=8.314 J.K-1.mol-1 F=96485 C.mol-1 T=25+273.15 z=+1 [K+]o=1 [K+]i=20 E=(RT/zF)ln([K+]o/[K+]i) E=(8.314 *298/(1*96485)ln(1/20) E=61ln(1/20)=-183mV
Thursday, February 7, 2013 at 1:28pm by Devron
Biochem
For membrane-associated proteins, the consensus sequence _______ is found on the inchoate (new) polypeptide and ______ to halt. a. pribnow, replication b. signal peptidase, transcription c. stop-transfer peptide, transcription d. stop-transfer sequence, translation e. stop-...
Tuesday, August 1, 2006 at 11:15am by Sarah
Biochem
Desribe the preparation of 2.00 L of 0.100M pH 9.00 glycine starting with the sodium chloride salt of zwitterionic glycinhe and 1.00M NaOh. If a reaction that generated 2.00 mmoles of base were carried out in 100 mL of the above buffer, what would be the final solution pH? ( ...
Tuesday, September 13, 2011 at 6:08pm by Sandra
Science
Since this is not my area of expertise, I searched Google under the key words "HIV 'reverse transcriptase'" to get these possible sources: http://en.wikipedia.org/wiki/Reverse_transcriptase http://www.cellsalive.com/hiv2.htm http://www.biochem.ucl.ac.uk/bsm/...
Thursday, January 3, 2008 at 7:07pm by PsyDAG
Chemistry - buffers
If that's all of it then your prof didn't give very good directions. I have no idea which acid he/she has in mind so I'll fly blind. I looked at the Ka values and picked HOCl. With pH = 8 for a buffer I might pick HOCl for the acid with Ka = 3.0E-8 (you need to see...
Monday, March 26, 2012 at 2:39pm by DrBob222
biology
Thank you for using the Jiskja Homewrk Help Forum. Try the following: `. http://en.wikipedia.org/wiki/Endergonic_reaction 2. http://library.thinkquest.org/27819/ch4_2.shtml 3. (part Ii of #3: http://library.thinkquest.org/27819/cgi-bin/quiz.cgi?quiz=4_2 4. http://www.emc....
Monday, February 11, 2008 at 12:24am by SraJMcGin
Biochem
pH = pKa + log (base)/(acid) Why not plug some number into the base and another number for acid and evaluate pH. If the number goes up you will have your answer and if it goes down you will have your answer.
Sunday, August 28, 2011 at 4:59pm by DrBob222
science... biology..
Thank you for using the Jiskha Hmework Help Forum. There are many and here are some: 1. http://www.biochem.northwestern.edu/holmgren/Glossary/Definitions/Def-C/cell_wall.html 2. http://www.thefreedictionary.com/cell+wall 3. http://www.answers.com/topic/cell-wall 4. http://...
Tuesday, October 14, 2008 at 3:24pm by SraJMcGin
biochem
I mixed 4.50mL of 10.0mM NaOH with .50mL phenol red. I need to calculate the pH of this solution. I have more information in my lab but I am not sure what data I need to look for. As part of the experiment I calculated pKa of Phenol Red. Do I use that pKa in the henderson-...
Tuesday, September 20, 2011 at 7:51pm by amy
biochem
How do you draw a tetrapeptide from the one letter codes(Amino acids) and also give the pI, if given the pKa values? For example the Amino acids: S,T,G,L So i know i decipher the the codes then to make tetrapeptide i start with the n terminus to the c terminus by adding the r ...
Tuesday, February 17, 2009 at 4:21pm by jeff helper
Biology
Since this is not my area of expertise, I searched Google under the key words "'substrate concentration' enzyme" to get these possible sources: http://ghs.gresham.k12.or.us/science/ps/sci/ibbio/chem/notes/chpt8/factorssubstrconc.htm http://www.worthington-...
Thursday, February 28, 2008 at 7:07pm by PsyDAG
biochem
There are just dilutions. You can use the dilution formula for most if not all. c1v1 = c2v2 c = concn V = volume 1.5M x v1 = 0.2M x 250 mL v1 = 0.2 x 250/1.5 = 33.33. So you place 33.33 mL of the 1.5M stock solution in a 250 mL volumetric flask, add water to the mark on the ...
Sunday, March 10, 2013 at 3:10pm by DrBob222
BioChem
Please help with this question. Insulin, antibodies, enzymes and progesterone are four of many molecules found in and around cells. Of these four__________ are/is not a protein. a. antibodies b. insulin and antibodies c. antibodies and progesterone d. progesterone I think the ...
Saturday, June 17, 2006 at 5:29pm by Jamshid
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