All Questions
516
questions
2
votes
2
answers
105
views
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 ...
- 39
-5
votes
1
answer
43
views
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 ...
3
votes
0
answers
27
views
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 ...
- 31
1
vote
3
answers
174
views
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/...
- 31
1
vote
2
answers
186
views
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 ...
- 247
-2
votes
1
answer
49
views
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, ...
- 93
0
votes
1
answer
79
views
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 ...
- 11
-5
votes
1
answer
106
views
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,...
1
vote
0
answers
28
views
Aquatic chemistry, pH and alkalinity
Hope you can help me with an aquatic chemistry question.
I have different types of water of different pH and alkalinity.
pH, alkalinity, HCO3 and CO2 concentrations are known.
I need to calculate the ...
- 11
0
votes
2
answers
144
views
Can carbonic acid form a salt with pH < 7?
Please read edit before answering
Background
I am currently studying in 10th grade. This question appeared in my science exam -
Which acid does not form an acidic salt?
Phosphoric acid
Carbonic acid
...
-4
votes
1
answer
61
views
Is it possible to make acids and bases in amphiprotic solvents other than water [closed]
In such solvents, could there be chemicals which could donate/accept protons, and if so could their solutions display acidic/basic properties?
- 1
-3
votes
2
answers
297
views
Can a multimeter be used to measure PH?
I would like to feed my garden a solution of water and Trisodium Phosphate (TSP), but I am uncertain of the correct amount of TSP to water ratio. Too acidic or too basic of a solution can harm my ...
- 874
0
votes
2
answers
167
views
dilution and pH and pOH
The question is: given a $10$ ml solution with pH = $12.3$, which is then diluted to a $100$ ml solution, find the pH of the new solution. My attempt was as follows:
[H$_3$O$^+$] = $10^{-12.3}$, and $...
- 109
3
votes
1
answer
155
views
Are there LCMS compatible buffer systems available for the high pH range 12-14?
I want to perform chemical stability studies for different pH Values. To achieve pH Values from 1 to 6 I can prepare solutions with trifluoric acid and formic acid and ammonium formate and acetate. I ...
- 779
-4
votes
1
answer
170
views
At 80 °C a solution having pH = 7 is? [closed]
When I came across this question I couldn't understand whether, they are asking the nature of solution at 25 °C which has pH = 7 at 80 °C or nature of solution at 80 °C which has pH = 7 at 25 °C ?
...
