Questions tagged [ph]
pH (or the potential of hydrogen) is a scale used to measure how acidic or basic an aqueous solution is.
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Why would the theoretical pH not match the measured pH when performing a titration of NH4OH with HCl?
I ran a weak base - strong acid titration experiment using an automatic titrator. I started with an aqueous ammonia stock solution (somewhere in the range of 0.1 - 2.5 wt.%) that was left open to ...
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Why should the pH change when I add sodium hydroxide to water? [closed]
I am a student and I am trying to understand the concept of pH.
If I add pure $\ce{NaOH}$ in water, it leads to the formation of $\ce{OH-}$ ions in the water. But this shouldn't lead to any change in ...
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Relative concentrations of ions in pure water with a pH of 7
Not a chemist here as the last Chemistry class I took was millennia ago, so please be patient with me. The Chem taught today is so different (and much harder) than I remember.
So, regarding pure water,...
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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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Experiment on pH vs Rate of Electrolysis - what do the results actually say?
My experimental setup looks at using different pH solutions (of $\ce{H2SO4}$ and $\ce{NaOH}$) for electrolysis of water with a Hoffman setup and then measuring the rate of production of gas (note this ...
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By how much does sodium bicarbonate raise pH?
I am a pool-maintenance and service worker. I’m a little new to the field; however, none of the technicians I work with seem to have a definite answer for me. When raising the alkalinity in pools, we ...
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pH at maximum concentration of a certain species (Phosphoric acid) [closed]
I am trying to find the pH at which $[H_{2}PO_{4} ^{-}]$ is maximum by only knowing the pKas.
I have tried to derive an equation using kinetics but it failed [1].
After taking a look at the Sillén/...
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Can I use pH test papers with a dye-rich solution?
I'm working on some lactic acid fermentation of blueberries at home, and I'm trying to get a better handle on the process by logging the pH of the fermentation medium as the fermentation takes place.
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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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How does the concentration of H+ ions in HCl change as the pH changes? [closed]
I am helping my friend's 16 year old prepare for her GCSE chemistry exam. This question was on an AQA GCSE Chemistry past paper but I do not know the year and could not find a markscheme for it on the ...
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What effect does the weak base have here?
Suppose we reacted enough strong base to fully neutralise a weak acid, clearly at this point (the equivalence point) the $pH$ would not be $7$. This is because the reaction between the strong base and ...
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Hydrolysis of $A_3B$ type weak acid-weak base salt
I know the formulae for weak acid-weak base salt of AB type. A peculiar question made me ask this. Do the formula for derived for AB type also hold for A3B type sal.
For example:
This is the question, ...
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Proper batch adsorption mechanism for heavy metals
I'm a college student with scope on environmental science, specifically the adsorption of heavy metals in aquatic media.
Currently, I suffered from serious issue of batch adsorption mechanism, which ...
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Change in pH/acidity of vinegar after adding aqueous NaCl
There's a question in my (grade 10) textbook asking to determine what will happen to the pH/acidity of vinegar if a solution of sodium chloride in distilled water is added to it drop by drop. The ...
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Find the pH of a solution obtained by mixing 100 ml 0.1m Na3PO4 and 100 ml 0.1 M NaH2PO4. Given that H3PO4: [Κα₁ = 10^-4, Κα₂ = 10^-7, Каз = 10^-11] [closed]
So, my query is that since NaH2PO4 is a weak acid, and Na3PO4 is a basic salt, wouldn't they react? Another theory was that since NaH2PO4 is a weak acid and Na3PO4 is a salt of strong acid and NaH2PO4,...
