Skip to main content

All Questions

0 votes
0 answers
31 views

Total concentration conversion

when dealing with waste water and the total values of P, N, C are given in ppm units, what molecular weight is used for converting from ppm to molar? for Example- what will be 12 ppm of P(T) in Molar ...
Efrat Brayer's user avatar
2 votes
1 answer
338 views

More ions form pairs when concentration of acid increases, does that decrease the speed of reaction?

Electrical conductivity decreases as an acid becomes more concentrated because more ions form pairs. However, does that affect the speed of reaction of the acid as there is a smaller concentration of ...
DrunkenKen's user avatar
-2 votes
1 answer
397 views

Notation for inclusion of water in a dissolution equation

Earlier I had a student come by wanting to know how to show the dissolution of $\ce{NH4OH}$ in water. I would think we would just write it: $$\ce{NH4OH(aq) <=> NH3(aq) + H2O(l)}$$ I say this as $...
neurosciencecalc's user avatar
5 votes
1 answer
2k views

Can you meassure a negative pH value with a pH meter?

I was checking the $\mathrm{pH}$ of $\pu{1 M}$ chromic acid solution, and I got its $\mathrm{pH}$ around -1.7. Yet, $\mathrm{pH}$ of $\pu{0.4 M}$ solution was around -0.6. Could these values be ...
marietiara's user avatar
4 votes
1 answer
226 views

Why is hydrated beryllium ion acidic?

The beryllium ion, $\ce{Be^{2+}}$, forms the aquo complex $\ce{[Be(H2O)4]^{2+}}$. According to LibreTexts, this complex is acidic in solution: $$\ce{[Be(H2O)4]^{2+} + H2O -> [Be(H2O)3OH]+ + H3O+}$$ ...
Ray Bradbury's user avatar
-1 votes
1 answer
513 views

How to calculate how much weak acid would dissociate in water?

So I know water has a pH of 7. If we add 0.1 mol of a strong acid inside 1 liter of water, it WILL fully dissociate into 0.1 mol of A- and 0.1 mol of H+ thus making the pH of the solution 1. But what ...
Bruno Machado's user avatar
0 votes
0 answers
550 views

Adding aluminum sulfate to neutralize an aqueous solution of sodium silicate with pH of 12.6

How much aluminum sulfate do I need to add to an aqueous solution of sodium silicate to neutralize the solution (pH from 12.6 to 7)? For a water treatment school project, we remove sodium silicate ...
Saif Taher's user avatar
3 votes
1 answer
4k views

Why does green ferrous sulfate solution change color to yellow upon addition of hydrochloric acid?

I was demonstrating the formation of $\ce{Fe(OH)2}$ precipitate at school when the light green $\ce{FeSO4}$ I was using reacted with dil. $\ce{HCl}$ turned yellow. This only happened with dil. $\ce{...
abrn2195's user avatar
  • 143
0 votes
0 answers
131 views

pH of an aqueous solution of Mg2+ kept rising above that of clean water. What's going on?

In a recent inorganic chemistry lab session, we tested the pH of various ions in water. The water turned out to be on the acidic side (5.5 with $\mathrm{pH}$-paper, 5.59 with $\mathrm{pH}$-meter). A ...
Quantonium's user avatar
5 votes
0 answers
187 views

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 $\pu{1M}$ ...
Araneus0390's user avatar
0 votes
1 answer
786 views

Why is the solution of ammonium bifluoride more acidic than aqueous ammonium fluoride?

At low concentrations of aqueous $\ce{NH4HF2}$ $(w = 1–2\,\%)$ $\mathrm{pH}\approx 3.$ But aqueous $\ce{NH4F}$ $(w = 20–40\,\%)$ has $\mathrm{pH}\approx 7.$ Yet the equilibria of $$ \begin{align} \ce{...
marietiara's user avatar
1 vote
1 answer
967 views

Dissociation equilibria of ammonium bifluoride in water

Ammonium bifluoride or ammonium hydrogen fluoride is a salt of a weak base and a weak acid. The weak acid is because the second equilibria of $\ce{HF}$ written as: $$\ce{HF + F- <=> HF2-}$$ and ...
marietiara's user avatar
7 votes
1 answer
4k views

Aspirin Hydrolysis at pH 2

Conducting an experiment, I found that very little salicylic acid was evolved performing hydrolysis at $\mathrm{pH \ 2}$ and at $\pu{45 ^\circ C}$. In fact, far more salicylic acid was evolved at $\...
Mas's user avatar
  • 467
-2 votes
2 answers
689 views

How is NaOH a base? [closed]

Firstly, how is $NaOH$ created? My teacher said that before it is $NaOH$, it is $NaO^-$. $$NaO^- + H_2O = NaOH + OH^-$$ If so, that means that $NaO^-$ is a base, which would make $NaOH$ it's conjugate ...
A. Kvåle's user avatar
  • 205
2 votes
2 answers
7k views

Preparation of ammonium acetate buffer for HPLC

Buffer solutions are typically prepared by dissolving an appropriate salt in water and then adjusting the $\mathrm{pH}$ to the desired position by addition of the conjugate acid or base. For example, ...
user103231's user avatar

15 30 50 per page
1 2 3
4
5
17