Questions tagged [aqueous-solution]

For questions relating to compounds dissolved in water and resulting reactions and acid-base equilibria.

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1answer
107 views

Equilibrium Constant of a Salt knowing the solubility

Calculate the equilibrium constant in $\ce\\M ^ 3$ of the heterogeneous system in aqueous solution: $\ce{CaF2 \leftrightarrows Ca^{2+} + 2F-}$ Knowing that the solubility of the salt is $15.9 \ce{mg/L}...
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2answers
6k views

Why does the ionic product of water remain constant after addition of non-neutral solute?

In my textbook, it is given that the ionic product of water $K_\mathrm{w}$ remains constant even when a non-neutral solute such as an acid is added to it. $$K_\mathrm{w} = \ce{[H3O+][OH-]}$$ When a ...
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1answer
2k views

How is tea affecting water's color?

Black tea is an amazing product of the green tea leaves. A recent study has proven that; The anion profile for the tea solution indicated that oxalate and citrate were the major anions detected. ...
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2answers
32k views

How is the dissolution of acetic acid that makes its aqueous solution a poor electrolyte?

I'm having a difficulty understanding the following quote from Wikipedia - Dissociation: Acetic acid is extremely soluble in water, but most of the compound dissolves into molecules, rendering it a ...
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2answers
8k views

How can an insoluble compound be a strong electrolyte

Here's a quote from Petrruci General Chemistry (pg. 160): Silver chloride, $\ce{AgCl}$ is an insoluble ionic compound. When $\ce{AgCl}$ dissolved in water, it is 100% dissociated into $\ce{Ag}^+\text{...
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2answers
6k views

Why is water a poor solvent for organic molecules?

Few organic molecules dissolve in water but why is this the case?
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5answers
14k views

Why is water “the universal” solvent?

This is an old question that our textbook tried to answer but worsened the situation. Many things are soluble in water. So many, that studying solutions will always require studying aqueous ones. It ...
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1answer
102 views

What other factors can make a compound dissolve into water?

I am doing some homework just right now, and I encountered this problem. I know that the polarity of the water molecules allows them to be a solvent for a variety of polar species or even species ...
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2answers
29k views

How to calculate the heat of dissolution from a calorimeter experiment?

A $\pu{1.50 g}$ sample of $\ce{KCl}$ is added to $\pu{35.0 g}$ $\ce{H2O}$ in a styrofoam cup and stirred until dissolved. The temperature of the solution drops from $24.8$ to $\pu{22.4 ^\circ C}$. ...
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1answer
1k views

Why do some solid chemicals dissolve better in colder water?

I just discovered that some solid chemicals, such as $\ce{Na2SO4}$, dissolve better in cold water than hot water from here and would like to know if there is any particular reason as to why. Is it ...
7
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1answer
6k views

Does iron(III) sulfate react with copper?

As my understanding, there should be an oxidation-reduction reaction: $$ \ce{2 Fe^3+ + Cu → 2Fe^2+ + Cu^2+} $$ However, I always see the process using $\ce{FeCl3}$ to etch copper, but I never ...
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1answer
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Where does the energy in the exothermic reaction of CaCl2 with water come from?

Today I created $1~\mathrm{M}$ aqueous solution of $\ce{CaCl2}$ and realized that the water before the mixture had a temperature of 23.4 Celsius degrees. Then I added the $\ce{CaCl2}$ and the ...
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1answer
139 views

Best x-ray dopant?

An x-ray computed tomography scanner has been used in an attempt to look at the pore space of a limestone rock sample (a carbonate, $\ce{CaCO3}$) saturated with a $\mathrm{12\ wt\%}$ sodium iodide ($\...
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2answers
18k views

How to predict the solubility of an organic compound in different kinds of solvents? [duplicate]

How is it possible to know whether a particular solvent will dissolve in a particular kind of solvent, i.e. organic, polar, protic...? Are there any indicators to look for in molecules or elements ...
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1answer
55k views

Preparation of iodine solution

How to prepare $\mathrm{0.1M}$ $\ce{I_2}$ solution. I have found in books that it should be prepared in $\ce{KI}$ solution but none of them explains why? Please explain in detail not just the ...
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1answer
348 views

Aqueous Chemistry: Ranking Ion Concentration

I am trying to rank the concentration of $\ce{PO4^3-}$, $\ce{NO3^-}$, and $\ce{Na+}$ that remain in a reaction. The reaction occurs when 100mL of 1.0M $\ce{Na3PO4}$ solution is mixed with 100mL of 1....
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1answer
429 views

Cyanide from seeds breaking down in a pond

I have a large loquat tree that overhangs a pond. The loquat seeds apparently contain cyanide of some sort, so I'm trying to find the effect the seeds have when they fall in the pond. Over time I ...
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1answer
604 views

What happens when oxidizing Ni(OH)2 with a strong base?

In an aqueous solution, Nickel oxyhydroxide is oxidised with a 1:1 ratio of aqueous Sodium hydroxide. My goal is to produce Nickel oxyhydroxide ($\ce{NiOOH}$). Strong Base: $\ce{NaOH + H2O \...
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2answers
361 views

chlorine formed in hydrochloric acid

Is it plausible that free chlorine could be formed in concentrated hydrochloric acid. The background to this is that I have bought some 30% HCl to remove calcium carbonate scale from a reverse ...
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2answers
1k views

What causes Starch's lump creation when solvent (butter/water/oil) is added and how to prevent them

When liquid(water/butter) is added to starch lumps of starch are formed. Which are completely dry from inside. Adding more solvent doesn't seem to help therefore it is not a case of saturated solution....
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1answer
2k views

Applying the Solubility Guidelines is AgClO4 soluble or insoluble?

The book I am using is "General Chemistry: Principles and Modern Applications by Ralph H. Petrucci. On page 158 the Solubility Guidelines for Common Ionic Solids is given. Rule 3 states that, "Salts ...
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1answer
648 views

Will I get bromine by electrolysis of the brine from the Dead Sea?

I know that electrolysis of a saturated solution of sodium chloride with an inert anode (eg., graphite) is a handy way to obtain pure chlorine. I have a sample of saturated salt solution from the Dead ...
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3answers
47k views

If caffeine is an alkaloid, why is coffee acidic?

I have just put together on my mind these two facts: caffeine is an alkaloid and brewed coffee is slightly acidic (pH = 5). My Biology teacher and my Chemistry teacher could not elaborate satisfying ...
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2answers
8k views

Why do acids ionize in solution if they are covalently bonded?

Maybe I am wrong, but I thought acids were covalently bonded since hydrogen doesn't form ionic compounds. For example, wouldn't $\ce{HCl}$ look like: Since the electrons are shared, why does it ...
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0answers
496 views

Reasonings on the pH of calcium carbonate in ammonium chloride solution

Consider calcium carbonate saturated in $1.0\:\mathrm{M}$ ammonium chloride solution. I have calculated the $\mathrm{pH}$ of this solution analytically (with mass and charge balance) to be $6.92$. ...
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1answer
53 views

Can we determine apriori the volume of solvent in an electrolyte

Suppose I would like to create a one molar solution of NaCl in water. The molar concentration is defined as $c_i=\frac{n_i}{V} $ $n_i=1$ in this case. I need to take 58.5 grams of NaCl (atomic ...
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1answer
804 views

How is the dichromate anion generated from potassium dichromate? [closed]

How does $\ce{K2Cr2O7}$ become $\ce{Cr2O7^2-}$ when dissolved in water?
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2answers
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Magnesium powder mixed with CuSO4 solution

$\ce{Mg}$ powder is stirred into $\ce{CuSO4}$, what is the balanced molecular equation for this reaction ? I have $\ce{Mg + CuSO4 -> Mg2SO4 + Cu}$. Also, is the ionic equation the same as the net ...
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3answers
2k views

What is the procedure to create stock solutions?

Until now to execute this recipe, each time i had to count those milligrams/Liter. An enough difficult procedure. I am posting here this question to help me understand the procedure of creating ...
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1answer
40k views

Net ionic equation with only aqueous ions

When you turn a balanced equation into a net ionic equation, you ignore all the ions that are spectator ions (aqueous on one side as well as the other). You only write the solid and the aqueous ions ...
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3answers
3k views

How to verify the accuracy of a pH meter

One suggestion I received is that I prepare a solution of a known activity and probe the solution with the pH meter. The problem I see with this is that any error in solution preparation can lead us ...
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1answer
3k views

Why is the water column empty in ICE table

In the ICE table pure solids and liquids have a value of one in the equilibrium expression but when we create an ICE table, why is the $\ce{H_{2}O}$ column empty? Should it not have a value of one?
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1answer
4k views

Removing HCl from water

I have water contaminated with dissolved chlorine: $\ce{H2O + Cl2 <=>HCl + HOCl}$ During electrolysis, this is an issue. These are my products: $\ce{NaCl + H2O ->T[electrolysis] NaOH + Cl2 ...
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1answer
3k views

Is 4-nitrobenzaldehyde or 4-aminobenzaldehyde more likely to be hydrated?

Of 4-nitrobenzaldehyde and 4-aminobenzaldehyde, which has the higher $\ce{K_{eq}}$ of hydration? $\qquad \qquad$ Steric factors can likely be ignored in this problem since we are dealing with ...
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3answers
6k views

How to calculate the solubility product for PbS from galvanic potential?

Knowing that at 25 °C the following galvanic cell: $$\ce{Pb~|~Pb(NO_3)_2~1M~||~PbS~saturated~|~Pb}$$ shows an $\mathrm{EMF} =0.413~\mathrm{V}$, find the $K_\mathrm{sp}$ of $\ce{PbS}$. My Approach ...
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0answers
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Identifying probable compound using its colour & reactants

This is quote from OxyChem document on Hypochlorites: Steel tanks in caustic soda service become passivated with a gray-black film forming on the metal. Thereafter, caustic soda at less than ...
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2answers
232 views

Can citric acid protonation produce benzene and water

Is this reaction possible: $\ce{C6H8O7 + 12 H3O -> C6H6 + 19 H2O}$? Considering that the $\ce{H+}$ can be induced by ionization of the citric acid solution the benzene can be produced in this way?
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1answer
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How does KMnO₄ affect electrolysis?

I'm just blindly experimenting. I tried to dissolve some potassium permanganate in water before performing electrolysis. I can't see much difference. How is $\ce{KMnO4}$ dissolved in water? How does ...
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1answer
4k views

What is the pH of a solution of HCOONa and HNO3?

Calculate the pH of an aqueous solution obtained by mixing 20 ml of $\ce{HCOONa}$ 0,1 M and 5 ml of $\ce{HNO_3}$ 0.2 M. ($K_\mathrm a$ of $\ce{HCOOH}$ $= 10^{-4}$) My try: The number of the ...
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1answer
720 views

Balancing ionic equations and determining number of ions

There were two questions that I've listed below that I've had troubles on. I got an answer in both, but both of them weren't correct. For the first question, they list the answer to be D and then ...
4
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1answer
76 views

Boiling solutions with two salts

If you dissolve two different ionic compounds (that don't make a precipitate) in water and then boil the solution so all the water evaporates, the salts will re-crystallize. Is it possible that you ...
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2answers
7k views

Why put zinc solution in a galvanic cell?

In a galvanic cell with Cu and Zn electrodes, I was taught that each electrode is immersed in a solution containing it's own positive ions. I understand why you need copper ions, so they can gain ...
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2answers
2k views

How can you predict a double displacement reaction with no precipitate?

Is it possible to predict a double displacement reaction between two ions where the products remain in aqueous solution? I see how you can predict precipitation reactions if you know whether the ...
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1answer
16k views

Acid-base equilibrium of NH4CN

I'm having difficulties understanding this problem. We have in the problem that $K_\mathrm a$ for $\ce{HCN} = 6.2\cdot10^{-10}$ and $K_\mathrm b$ for $\ce{NH3} = 1.8\cdot10^{-5}$. Write chemical ...
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1answer
2k views

Byproducts of the neutralisation of hydrochloric acid with sodium hydroxide

Given a 1 M concentration of $\ce{HCl}$ and $\ce{NaOH}$ here are the pHs: pH of $\ce{HCl}$: 1 pH of $\ce{NaOH}$: 13–14 and of course water has a pH of 7. Here is a reaction that is most likely to ...
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1answer
1k views

Calculating Ka values from std. state thermodynamic data

My professor showed us a sample calculation of the Ka value for a strong acid. He used standard state thermodynamic data. I have an issue with this: 1) Wouldn't this give us an understated Ka value?...
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3answers
600 views

What does the hydrolysis of a salt tell us about its basic/acidic character?

I'm curious to know how basicity and acidity arises when a salt or covalent compound is dissolved in water.
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2answers
47k views

Neutralization reaction between ammonia and nitric acid

Complete and balance the following molecular equation (in aqueous solution); include phase labels. Then, write the net ionic equation. $~\ce{NH_3 + HNO_3 -> ?}$ I thought that the acid $\ce{HNO3}$ ...
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4answers
49k views

How much can the pH change through dilution?

Consider an acidic solution with Hydrogen ion concentration, $\ce{[H+]}$ of $10^{-5}\:\mathrm{M}$. Since $\:\mathrm{pH} = -\log \ce{[H+]}$ the $\:\mathrm{pH}$ of solution is $5$. Suppose we dilute ...
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0answers
182 views

Deviation from ideal solutions - activities and concentrations

What are some examples of solutions deviating significantly from ideal behavior, and, by extension, showing pHs significantly different from those predicted by usage of concentrations instead of ...