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2 votes
1 answer
67 views

Does solubility product dictate predominant precipitate from the solution with several ionic compounds?

While removing temporary hardness through boiling, magnesium bicarbonate will give $\ce{Mg(OH)2}.$ $\ce{Mg(OH)2}$ predominates over $\ce{MgCO3}$ as the solubility product $K_\mathrm{sp}$ of $\ce{Mg(OH)...
Avaneesh B's user avatar
1 vote
1 answer
107 views

Why does balancing the oxidation of dichromate(VI) to chromium(III) require six iron atoms?

The problem: Balance the following chemical equation using oxidation numbers: $$ \ce{Fe^2+ + Cr_2O_7^2- -> Fe^3+ + Cr^3+} $$ What I have tried: $$\ce{\overset{+II}{Fe}^{2+}(aq) + \overset{+VI}{Cr}...
Nora's user avatar
  • 133
2 votes
2 answers
316 views

My textbook writes hydronium ion as [H(H2O)]+, is this correct? [closed]

[...] Thus, it bonds to the oxygen atom of a solvent water molecule to give trigonal pyramidal hydronium ion, $\ce{H3O^+}$ $\ce{\{[H (H2O)]^+\}}$ (see box). In this chapter we shall use $\ce{H^+(aq)}$ ...
Hdje's user avatar
  • 127
0 votes
1 answer
475 views

Why does balancing the reduction of dichromate(VI) to chromium(III) require four water molecules among the products?

Problem Balance the following chemical equation using oxidation numbers: $$\ce{Cr2O7^2–(aq) + HNO2(aq) –> Cr^3+(aq) + NO3–(aq)}$$ Solution (in Swedish) $$\ce{\overset{+VI}{Cr}_2O7^2–(aq) + H\...
Nora's user avatar
  • 133
2 votes
4 answers
172 views

How can the Kw of water be constant?

I know in neutral solution, $\ce{[H+]}= \ce{[OH-]}= \pu{1.0 x 10^-7}$. However, let’s say I add an acid like HCl. This will increase $\ce{[H+]}$, therefore it’s no longer $\pu{1.0 x 10^-7}$, but is ...
Maria's user avatar
  • 41
1 vote
1 answer
157 views

Solubility of SrF2 in aqueous solution of NaF

This might be really simple question but I have no idea how to proceed to solve such kind of question. The solubility product of $\ce{SrF2}$ in water is $\pu{8E-10}$. Calculate its solubility in 0.1M ...
izack's user avatar
  • 23
2 votes
1 answer
103 views

Equilibrium Solubility of CO2 in Aqueous Solution and its Dependence on H3O+ Concentration

The equilibrium solubility of $\ce{CO2}$ in an aqueous solution is given by three chemical reactions: $$ \begin{align} \ce{CO2(g) &<=> CO2(aq)}\label{rxn:R1}\tag{R1}\\ \ce{CO2(aq) + H2O &...
Lineare Libelle's user avatar
-4 votes
2 answers
88 views

Successive deprotonation - how far can it go?

It has been written that among the equilibria of the dissolution of $\ce{SO_2}$ in water, the dissociation of sulphur dioxide into $\ce{HSO_3^-(aq) + H_3O^+(aq)}$ is a complete dissociation. See the ...
user110391's user avatar
0 votes
1 answer
74 views

Why does the reaction of dissolution stop at an equilibrium point? [closed]

The formula for Gibbs free energy is $\Delta G=\Delta H-T\Delta S$. If Gibbs free energy is negative, the reaction is spontaneous. This also applies to dissolution reactions. However, we know that ...
trigress09's user avatar
3 votes
2 answers
2k views

Calculate the titer of a solution

I hope this is the right place to ask. We have this exercise without solution One litre of diluted sodium hydroxide solution (c = 0.15mol/litre) is to be prepared in the laboratory. The titer from ...
wengen's user avatar
  • 423
1 vote
1 answer
105 views

What is the maximum number of silver(Ⅰ) ions in one litre of a 0.003 M sodium sulfide solution?

What is the maximum number of silver(Ⅰ) ions that can be present dissolved in one litre of a $\pu{0.003 M}$ $\ce{Na2S}$ solution? According to my book, silver(I) reacts with sulfide producing $\ce{...
wengen's user avatar
  • 423
1 vote
0 answers
69 views

Would a container made of sugar eventually dissolve if filled with a sugar-saturated solution of water?

Suppose you had a bottle made of sugar glass, and filled it with water that was already saturated with sugar. I know that with a fully saturated solution of sugar in water, no additional sugar can ...
Isaac Philo's user avatar
-3 votes
2 answers
246 views

Calculate the concentration of HF in aqueous solution of NH4F and NH4HF2 mixture

There is a similar question on this site, but here i have a mixture. I have a mixture of NH4F (35% weight) and NH4HF2 (8% weight) in water. How do I calculate the weight % expressed in HF? or the ...
Ale's user avatar
  • 1
2 votes
2 answers
147 views

Find the added volume of HCl so that the ions separate

Suppose we have a 10mL solution that contains 0.02M $\ce{Ag^+}$ and 0.04M $\ce{Ba^{2+}}$. a) Find the necessary volume to be added of $\ce{HCl}$ to separate all the silver. (Assume to be separated if ...
Aley20's user avatar
  • 53
-1 votes
1 answer
114 views

Why phenolphthalein is not completely neutralized in basic solutions? [closed]

Phenolphthalein $(\ce{HIn})$ is slightly acidic. Why doesn't it completely break down into $\ce{H+}$ and $\ce{In-}$ and also reacting with all of the $\ce{OH-}$ ion present, unlike $\ce{NaOH}$ and $\...
dandelionseeds's user avatar
1 vote
2 answers
262 views

What is the significance of charge balancing when analysing system speciation (carbonate system given as an example)?

Following on from my previous question and accepted answer, How do I quantify the carbonate system and its pH speciation?, I also calculated a charge balance ($CB$) on the system where $z$ is the ...
Hendrix13's user avatar
  • 500
4 votes
1 answer
1k views

How do I quantify the carbonate system and its pH speciation?

I did Environmental Water Chemistry as part of my undergraduate course where we quantified pH-speciation for the full carbonate system and I got it right according to my tutor. My speciation profile ...
Hendrix13's user avatar
  • 500
1 vote
1 answer
122 views

How to find ion concentrations at various points in a solution that will precipitate multiple insoluble salts?

The solubility product constant of lead (II) iodide is $1.2 \times 10^{-5}$ at 273 K. The solubility product constant for lead (II) carbonate is $1.5 \times 10^{-13}$ at the same temperature. 50 ...
user avatar
1 vote
0 answers
305 views

Chemical Equilibrium of the Esterification Reaction Between Propanol and Ethanoic Acid

I am trying to investigate the relationship between temperature and equilibrium constant of the esterification reaction between propanol and ethanoic acid in reflux system, with conc. sulphuric acid ...
昨晚忘記呼吸's user avatar
0 votes
0 answers
72 views

Finding dissolved amount of base from pH and solubility product

Calculate the amount of $\ce{Mg(OH)2}$ which is solubilized in $\pu{1.25 L}$ of a buffered solution at $\mathrm{pH} = 9.5$. $(K_\mathrm{sp}(\ce{Mg(OH)2}) = \pu{5.61E-12})$. From $\mathrm{pH}$ I ...
Rick88's user avatar
  • 109
1 vote
1 answer
70 views

An Index Poisoning Case Involving Dichlor and Carbonic Acid [closed]

I'm currently working an unusual case of poisoning, with Sodium Dichloro-S-Triazinetrione. In my case, I need to know the expected reaction with carbonic acid. I'm also curious if anyone could give ...
Excallibro's user avatar
1 vote
1 answer
480 views

Acid dissociation constant calculated from the ionization percentage

The question goes like this: An acid (HX) is 25% dissociated in water. If the equilibrium concentration of HX is $\pu{0.30 M}$, calculate the value of $K_\mathrm{a}$. So I tried as follows: if I ...
Wagner Coelho's user avatar
2 votes
1 answer
318 views

Relation between standard silver-silver chloride electrode potential and solubility product of silver chloride

I learned that $E^\circ_\ce{Cl^-|Ag,AgCl}, E^\circ_\ce{Ag^+|Ag}$ and $K_\mathrm{sp}$ of $\ce{AgCl}$ are related as $$\boxed{E^\circ_\ce{Cl^-|Ag,AgCl} = E^\circ_\ce{Ag^+|Ag} + \frac{RT}{F}\ln K_\mathrm{...
Ray Bradbury's user avatar
9 votes
2 answers
959 views

Numerically solving chemical equilibrium equations

Here are chemical equilibrium equations: $\begin{cases} \mathbf{N}^\text{T}\mathbf{X}+\mathbf{C}=\mathbf{Y}\\ \mathbf{N}\ln\mathbf{Y}=\ln\mathbf{K} \end{cases}$ Here $\mathbf{C}=\begin{pmatrix}c_1\\...
auntyellow's user avatar
1 vote
1 answer
366 views

Calculating pH of aqueous ammonium hydrogen sulfide solution

I was doing the following question yesterday: Calculate the pH of a $\pu{0.1 M}$ solution of $\ce{NH4HS}$, given $\mathrm{p}K_\mathrm{b}$ of $\ce{NH3}$ is $4.74$, and $\mathrm{p}K_\mathrm{a1}$ and $\...
Adithya's user avatar
  • 1,411
-1 votes
1 answer
199 views

How are acids in aqueous solution able to react again after reacting with water?

I hope to clear up some confusion I have about acid-base reactions in aqueous solution. Based on the Bronsted-Lowry definition of acids, I know acids donate protons. In water, a strong acid should ...
Srihari P's user avatar
0 votes
0 answers
66 views

Osmotic Pressure of Aqueous Solution

The osmotic pressure of an aqueous solution at $25$ Celsius is $92.0$ $kPa$. Calculate the boiling point of the solution. (Assume that the density of the solution is $1.0$ $g/mL$, ignore the mass of ...
Snowball's user avatar
  • 117
0 votes
0 answers
74 views

Equilibrium of zinc ion with ammonia

In my chemistry lab, we are testing the amphoteric properties of this metal. I understand zink can react with an acid or a base to form different compounds in solution based on pH. In one part of the ...
DJames's user avatar
  • 1
1 vote
0 answers
101 views

Physical Chemistry: Specifically the Dissolution of Carbonates

Please note this question is different to the other that keeps being mentioned. That one is about the concentration of just $\ce{HCO3-}$ when no $\ce {pH}$ was given. Whereas, in this one I am trying ...
Edward's user avatar
  • 51
0 votes
0 answers
126 views

Why is the Ag+ concentration in a beaker fixed in the reaction between excess AgCl (s) and KI (aq) from the start? [duplicate]

This arises as a sub-question for the following question: Calculate the concentration of I- in a solution obtained by mixing 0.10 M KI with an excess of AgCl(s). I tried to look at How does addition ...
chemcurious's user avatar
0 votes
2 answers
1k views

How does addition of AgCl affect concentration of iodide in KI solution?

In a mixture of $\ce{AgCl(s)}$ and initial $\pu{0.10 M}$ $\ce{KI}$, what is the $[\ce{I-}]$ after the reaction proceeds? Disclaimer: This is not a graded assignment, but rather a problem I'm trying to ...
user105739'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
2 votes
1 answer
987 views

How to calculate molar concentration from equilibrium equations with no initial concentration given?

I have the equations: \begin{align} \ce{CO2(g) + H2O(l) &<=> H2CO3(aq)} &\quad K_1 &= 10^{-1.47} \tag{1}\\ \ce{H2CO3(aq) &<=> H+(aq) + HCO3-(aq)} &\quad K_2 &= 10^{-...
Edward's user avatar
  • 51
0 votes
1 answer
38 views

Disparity between LeChatelier's Principle and Solutions

Let's say that there is a solution $\ce{Na+(aq) + Cl-(aq) <=> NaCl(s)}$ If the above solution is at equilibrium we can say that it is saturated and hence no more Sodium Chloride will dissolve. ...
An0n1m1ty's user avatar
  • 151
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
2 votes
2 answers
116 views

Criterion for gravimetric analysis of silver

If the only criterion for gravimetric analysis of silver is solubility of precipitate, which one of the following two compound are we supposed to choose? $K_\mathrm{s}(\ce{AgCl}) = \pu{1.78E-10}$ and ...
OthersAl's user avatar
2 votes
0 answers
56 views

Calculating the solubility for chromium(III) hydroxide using the complex ion constant

Problem $$ \begin{align} \ce{Cr(OH)3(s) &<=> Cr^3+(aq) + 3 OH-(aq)} &\quad K_\mathrm{sp} &= \pu{6.7E-31} \\ \ce{Cr^3+(aq) + 4 OH-(aq) &<=> Cr(OH)4-(aq)} &\quad K_\...
T.Mok's user avatar
  • 31
1 vote
2 answers
1k views

Does carbonation permanently increase the acidity of soda water?

If you carbonate water, and then expose the resulting soda water to the atmosphere and wait until it goes completely flat, will the (former) soda water end up more acidic in final equilibrium than ...
tparker's user avatar
  • 121
0 votes
0 answers
138 views

Problem in the calculation of ionic strength of a solution

Recently I've been trying to answer the question 10-13 (c) of 9th edition of Fundamentals of Analytical Chemistry of Skoog et al. Comparing my answers with the student manual , I realized that my ...
Amirreza Mousavi's user avatar
0 votes
1 answer
271 views

Why are some weak acid equilibrium approximations invalid in very dilute solutions?

Using two approximations for the dissociation of a weak acid, we can write $$K_\mathrm{a}= \frac{[\ce{H+(aq)}]^2}{[\ce{HA(aq)}]}$$ One of these two approximations we use is that the concentration of ...
XXb8's user avatar
  • 209
-3 votes
1 answer
5k views

pKa = pH for strong acid — strong base?

I have learnt that for a weak acid — strong base titration, $\mathrm{p}K_\mathrm{a} = \mathrm{pH}$ at the half equivalence point. However, the same conclusion is not drawn when discussing strong acid —...
vgupt's user avatar
  • 153
5 votes
1 answer
403 views

Common Ion Effect - Ionic Equilibrium

Question In which of the aqueous solutions of the following, dissociation of $\ce{NH4OH}$ will be minimum? A) $\ce{NaOH}$ B) $\ce{H2O}$ C) $\ce{NH4Cl}$ D) $\ce{NaCl}$ My Thoughts My book says that ...
InfiniteCool23's user avatar
0 votes
0 answers
115 views

Effect of adding an acid or base to water with respect to concentration of ions

So I know that there's auto-ionization of water according to: $$\ce{2H2O <=> H3O+ +OH-} \tag{1}$$ If I have pure water where the concentrations of both $\ce{H3O+}$ and $\ce{OH-}$ is $10^{-7}$ ...
Stephen Alexander's user avatar
-1 votes
1 answer
512 views

An equilibrium question involving mixing equal volumes of HCl and H2SO4

Question: Calculate the concentrations of H3O(+) and SO4(2-) in a solution prepared by mixing equal volumes of 0.2M HCl and 0.6M H2SO4. (Ka1 for H2SO4 is very large, and Ka2 for H2SO4 is 1.2E-2) Here ...
Yan Qin's user avatar
  • 65
0 votes
4 answers
572 views

How many grams of sodium phosphate must be added to precipitate as much of one ion as possible?

Problem text: Solid sodium phosphate is slowly added to $\pu{200 mL}$ of a solution containing $\pu{0.002 mol}$ of aluminum chloride and $\pu{0.001 mol}$ of calcium chloride (assuming no volume ...
Kamran Poladov's user avatar
0 votes
2 answers
712 views

How to calculate mass of calcium fluoride that will dissolve in sodium fluoride solution?

The solubility product of calcium fluoride, $\ce{CaF2},$ is $\pu{1.46E-10 mol^3 dm^{-9}.}$ What mass of calcium fluoride will dissolve in $\pu{500 cm^3}$ of $\pu{0.10 mol dm^{-3}}$ sodium fluoride ...
gc3941d's user avatar
  • 145
2 votes
2 answers
2k views

Equilibrium involving both gas phase and aqueous phase

If I have been given an equation that involves a gas-aqueous phase equilibria, how do I write the equilibrium constant? I have come across several questions that give equations having BOTH gas and ...
Vamsi Krishna's user avatar
-1 votes
1 answer
2k views

How to calculate the amount of water required to increase the pH of a solution from 2.1 to 4? [closed]

After working out the problem with certain approximation of considering the initial pH=2, my answer came out to be around 1 litre of water. But the correct answer is 79 litres of water. Can anyone ...
Adrika De's user avatar
1 vote
3 answers
314 views

How to decrease the percent of ammonia that is converted to the ammonium ion in water? [closed]

Ammonia is a weak base that reacts with water according to this equation: NH3(aq) + H2O(l) ⇌ NH4+(aq) + OH −(aq) Will Fe(NO3)3 decrease the ...
Tiago Peres's user avatar
-1 votes
3 answers
1k views

Are aqueous (aq) elements involved in equilibrium?

The reaction was something like this: A (s) + B (l) yields to C (aq) + D (aq) The question asked: If you added another D, which way would the equilibrium shift to? I answered that it would have no ...
Ello's user avatar
  • 1

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