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See the Web Links to the left of this answer.
I especially like the Smith.edu link -- it has complete and very useful description of how to prepare a buffer.
Use the Henderson-Hasselbach equation:pH = pKa + log [A-]/[HA]
where HA is the protonated form of the weak acid, A- is the salt (dissociated acid, or in other words, its conjugate base), and the pKa is the strength of the acid.
What this says is that the pH that you want your buffer to be depends on two things:
-- the pKa of the weak acid you are using (see reference tables under the Web Links to the left)
-- and the RATIO of the concentration of the acid and the salt that you add to the solution.
The pH of the buffer does not depend on the actual concentration of the buffer, but on the ratio of the two parts.
The buffer capacity depends on two things -- how close to the pKa the pH of the buffer actually is (it should be within 1-2 pH units), and what the total concentration of the buffer is.
For instance if you have 0.001 M acetic acid and 0.001 M sodium acetate, the resulting buffer will have the exact same pH as a buffer made with 0.1 M acetic acid and 0.1 M sodium acetate (because the ratio is 1 to 1, the pH = pKa = 4.76). However, the 0.1 M buffer will have a much larger buffer capacity, and will much better resist changes in pH upon the addition of a strong acid or base.
Wiki User
∙ 16y ago
Wiki User
∙ 15y agoFind a buffer at a reasonable buffering range (a pH of 4 or 7 is typically used as a standard). The pKa of the buffer does not have to be exactly the number you are looking for, but it should be close. Next use the henderson-hasselbach equation to find the ratio of weak acid to conjugate weak base to use in solution to get your desired pH.
Wiki User
∙ 12y agoCombine volumes of equal molar mono- and di- basic phosphate solutions
For example, 15.9 mls .2M monobasic sodium phosphate + 284.1 mls .2M dibasic sodium phosphate + 300mls water will give you a pH 8.0 .1M solution.
Wiki User
∙ 15y agoUse the henderson-hasselbach equation. pH = pKa + log([A-]/[HA])
Wiki User
∙ 6y agoI need to make solutions of pH 6.47, 8.41 and 10.35. How would I do this?
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How do you prepare phosphate buffer of pH 7.5?
See the Related Links for "Columbia.edu: Phosphate buffer automatic calculator" to the bottom for the answer.
How do you make 50 mM potassium phosphate buffer pH 7.4?
1 M Sodium Phosphate Buffer Stock Solution (1 liter) Protocol # Solution A: Dissolve 138.0 g NaH2PO4?H2O in 1 liter dH2O (pH 7.0). # Solution B: Dissolve 142.0 g Na2HPO4 in 1 liter dH2O (pH 7.0). # Mix 423 ml Solution A with 577 ml Solution B. # Autoclave and store at room temperature.
How do you prepare 20 mM citrate phosphate buffer of PH 7?
10ml of 0.4M Citric acis solution 90 ml of 0.4M sodium phsophate dibasic solution 12.22g NaCl (tomake 150mM ionic solution) or 6.38g to make 100mM ionic strength. make up volume upto 2000ml with water. You should not need to pH this buffer . :)
Why use a phosphate buffer in the lab?
The PBS solution is necessary to check the stability of materials that will be used for biological purposes.
Why is the phosphate buffer made up by using the Henderson hasselbalch equation not the expected PH?
1. Why is the phosphate buffer made up by using the Henderson-Hasselbalch equation not the expected pH?
How to prepare phosphate buffer pH 5.8?
preparation of 5.8 ph phosphate buffer
How I can prepare 5 mM phosphate buffer?
5 mM phosphate buffer (4.82 g/l monohydrate, monosodium phosphate, pH 6.5).
How do you prepare phosphate buffer of pH 7.5?
See the Related Links for "Columbia.edu: Phosphate buffer automatic calculator" to the bottom for the answer.
How do you prepare phosphate buffer PH 6.8?
dissolve the 12 g of crystals of sodium phosphate in water to make 1oo ml
How do you make 50 mM potassium phosphate buffer pH 7.4?
1 M Sodium Phosphate Buffer Stock Solution (1 liter) Protocol # Solution A: Dissolve 138.0 g NaH2PO4?H2O in 1 liter dH2O (pH 7.0). # Solution B: Dissolve 142.0 g Na2HPO4 in 1 liter dH2O (pH 7.0). # Mix 423 ml Solution A with 577 ml Solution B. # Autoclave and store at room temperature.
How do you prepare 20 mM citrate phosphate buffer of PH 7?
10ml of 0.4M Citric acis solution 90 ml of 0.4M sodium phsophate dibasic solution 12.22g NaCl (tomake 150mM ionic solution) or 6.38g to make 100mM ionic strength. make up volume upto 2000ml with water. You should not need to pH this buffer . :)
How do you make a sodium phosphate buffer solution of pH 6.8?
For pH = 7,0: 756 mL disodium hydrogen phosphate (Na2HPO4) solution 0,1 M (14,2 g/L) + 244 mL hydrochloric acid (HCl) solution 0,1 M
What is the function of PBS buffer?
The main function of PBS (phosphate buffer saline) is to maintain the pH of the solution. by Himanshu Goel Jaypee University of Information Technology
How do you make this solution?
I don't know how to make the solution below. Low salt buffer: 10 mM phosphate buffer, 10 mM NaCl, pH 7.4. Could you tell me the method in detail?
A solution that is resistant to change in pH?
Solutions that resist change in pH when added to a strong acid or base are known as buffer solutions.
How you can do stability of Ranitidine infusion?
Jst keep the solution in the pH range 6 to 7 with a phosphate buffer..... Thanks, Bidya Sekhar
How do you prepare tris-hcl buffer solution of 0.5M?
6g Tris HCl + 100ml dH2O, pH 6.8
