Questions tagged [buffer]
Use for questions regarding solutions containing a mixture of a strong acid and weak base or vice versa.
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questions with no upvoted or accepted answers
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What pH value of 1M sodium crotonate solution supposed to be?
I need to prepare the $\pu{1M}$ solution of sodium crotonate, however, I don't have one in lab, but I do have sodium hydroxide and crotonic acid.
Thus, I calculated that for $\pu{100 mL}$ of $\pu{1M}$ ...
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Non-binding buffer at pKa of roughly 6 that dissolves in ethanol?
I'm trying to find a proper buffer for my experiment, which I'd appreciate some suggestions on. I have a solution in which I want to measure the concentration of magnesium ions using a fluorescent ...
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Assessing stability of protein used for interaction experiments after changing buffer from tris to HEPES
I have a protein with a theoretical $\mathrm{pI}~9.0$ currently stored in $\pu{25 mM}$ tris and $\pu{250 mM}$ $\ce{NaCl}$ $(\mathrm{pH}~8)$ at $\pu{−80 °C}.$ I need to do experiments in HEPES at $\...
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Measuring [A-]/[HA-] with Buffer and Indicator
I'm very confused on how to calculate the [A-]/[HA] value, given the fact that my dilution series uses buffers at various pH values with the same indicator (supplied at the same concentration to each ...
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Stability of n-Dodecyl-beta-D-maltoside in buffer solutions for assay experiments
I have a buffer system which contains multiple salts and in addition DTT and n-Dodecyl-beta-D-maltoside.
I understand that DTT is hydrolysing quite fast and this component must be used always fresh ...
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Why do buffer solution only maintain pH to a certain limit?
I know that buffers have a capacity after which they are not able to maintain a relatively stable pH. This capacity is exceeded when we add too much acid or base but I was wondering why does this ...
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How to determine the pH of citrate buffer system
I used this table (http://microscopy.berkeley.edu/Resources/instruction/buffers.html) to make a citrate buffer system. The Pka value is 6.4, and I multiplied the solution by ten to make a larger batch....
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Exact calculation of pH of diprotic acid plus strong base
Another post has an excellent "exact" calculation for the [H+] (or pH) of a generic diprotic acid dissociating in water.
Combining acid dissociation constants to determine pH of diprotic ...
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Can addition of a "neutral" salt like NaCl assist pH test strip measurement accuracy in low ionic strength/poorly buffered solutions?
After a web-search, it seems ISAs (Ionic Strength Adjusters) are offered commercially to assist pH electrode/probe measurements. Presumably meant to increase conductivity (without affecting pH ...
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How strongly affected is the buffering capacity of sodium carbonate - sodium bicarbonate by temperature changes?
I would like to do a lab regarding the affects of temperature on the buffering capacity of sodium carbonate - sodium bicarbonate in particular for sulfuric acid. Currently I have two competing ...
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Which is more effective at raising pH, Tums or baking soda?
Chemical buffers like Tums (calcium carbonate) and bases like baking soda (sodium bicarbonate) are both used medically to reduce acidity in the stomach to ease heartburn symptoms. I'm curious which is ...
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Stable physiological buffer to make NAD+ solution
I was wondering what would be the most stable physiological buffer for nicotinamide adenine dinucleotide (NAD+), for potential storage as frozen aliquots - 6 months stability or around there would be ...
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Does temperature affect ionic strength?
Hello I apologize if this is a dumb question but if I have a phosphate buffer made up of Na2HPO4 and NaH2PO4 and I gradually increase the temperature (lets say 10,20,30,40,50) what would happen to the ...
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How to calculate the buffer capacity for polyprotic acids? specifically H2PO4 --- HPO42- + H30+
as the title says. Is b= amount of OH-/ H3O divided by volume of buffer x change in pH wrong to use with polyprotic acids? Can I calculate the buffering capacity of a sodium phosphate buffer made up ...
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Calculating acid volumes needed
I collect water quality samples used for irrigation. The samples are sent to a lab to measure $\ce{Ca^{2+}, Mg^{2+}, CO3^{2-}, HCO3^-}$, pH, and total dissolved solids.
I need to use acid to prevent ...
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