Recent content by vande060

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    What are ions of molecules interacting with in vivo

    For example: amino acids that are floating around, some with charge at physiological pH. My question is what exactly do the charged amino acids form a salt with? other amino acids? sugars? fatty acids? whatever happens to have an opposite charge and is close? A rephrasing: I am thinking...
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    Is Citric Acid Fully in Conjugate Base Form at pH >5.41?

    Homework Statement just a curosity of mine. citric acid is triprotic, with a pKa3 of 5.41, so does this mean that i will be inf ull conjugate base form(3-) at solution pH >5.41 Homework Equations The Attempt at a Solution
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    Solve 5pH Solution from Citric Acid (1L)

    Homework Statement how would you make a 5pH solution from citric acid(1L) Homework Equations pH= log(H+) The Attempt at a Solution So I will try to work backwards from the [H+] antilog(-5) = 10^-5 M H+ needed this number can be divided by 3, because citric acid is...
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    What is a duplicate sample when preforming a photometric protien assay

    what is a"duplicate sample" when preforming a photometric protien assay Homework Statement Q: How do you prepare duplicate samples? Why is it important to run samples in duplicate of triplicate? what is a"duplicate sample" when preforming a photometric protien assay? Homework...
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    Preparing 40mM TES pH 7.4 - Calculating A-/HA

    whoops it should be 44% converted to base
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    Preparing 40mM TES pH 7.4 - Calculating A-/HA

    so I would go: 229.25g/mol * .04moles/liter *.1L = .917g TES added then to calulate strong base needed to convert 56% of acid to base .04moles/liter *.1L = .004 moles TES * .56 = .00224 moles of strong base needed
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    Preparing 40mM TES pH 7.4 - Calculating A-/HA

    Thank you, Ok, that's kind of what I thought. So the acid MW is 229.25, and the base would be (229.25 - 1.008) is that correct?
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    Preparing 40mM TES pH 7.4 - Calculating A-/HA

    Homework Statement prepare 40mM TES buffer pH 7.4 prepare 100mls of it mw TES = 229.25 pka = 7.5 Homework Equations ph = pka +log(A-/HA) The Attempt at a Solution My problem is that I don't know what the MW of the acid or base is for this buffer. Is the given MW the...
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    Chemistry colution prep question (quick)

    Homework Statement I have to dissolve phenylthiourea in a phosphate buffer solution. The final molarity of the phenylthiourea is 10^-5, but it says to dissolve it in ethanol. Does this mean that I have to dissolve my weight of phenylthiourea in a minimal amount of ethanol, then bring that to...
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    A couple questions about the bradford method

    Is it that one of the blanks is left with water to zero the machine and the other blank has just coomassie brilliant blue added to it, measured for absorption, and then subtract the absorption from the standards when plotting the standard curve, because that is what I am told to do for my...
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    A couple questions about the bradford method

    Homework Statement In the protocol for the bradford method I am told to prepare two blanks of water of .15M NaCl. I don't understand why I need two of them. Don't I just need one of them for placing into the photometer after I have set 0% transmission to set 100% transmission by. should...
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    Molar extinction coefficent calculation

    WE are doing it by making a standard curve, I think this was more of an exercise. I'll try to find good literature to cite the correct calculation of the EC by, otherwise I'm going with using the peptide sequence he gave us. Thanks so much for clearing that up
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    Molar extinction coefficent calculation

    Homework Statement I am to calculate the molar extinction coefficient for Bovine serum albumin Homework Equations ε = (nW×5500) + (nY×1490) + (nC×125) for coefficients around 280nm The Attempt at a Solution I know how to solve this by adding up the tryptophan, tyrosine, and cytosine for...
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    Efficient Buffer Preparation: 500ml MgCl2, Glucose, ATP, and Tris-Cl at pH 7.8

    Homework Statement Prepare 500ml of a reaction buffer containing .82% MgCl2, 62.5 mM glucose, 950 ATP, and 100mM Tris -Cl, pH 7.8 Use the stock solutions you have prepared we had to prepare in previous problems: 500ml 1.75M glucose 25mL 2.5% glucose 2L of 1.8 Tris, pH 8.5...
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