For questions relating to compounds dissolved in water and resulting reactions.

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12 views

Mg(OH)2 + 2HCl --> MgCl2 + 2H20 with .933 moles of Mg(OH)2 and 2.34 moles of HCl which is the limiting reagent [on hold]

If you have a balanced equation $$\ce{Mg(OH)2 + 2HCl -> MgCl2 + 2 H2O}$$ and .933 moles $\ce{Mg(OH)2}$ and 2.34 moles $\ce{HCl}$, which is the limiting reagent and how?
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0answers
21 views

density of potassium bromide

I'd like to know the density and viscosity of aqueous KBr at varying concentrations and at varying temperatures. I was able to find this data at 20 degrees C in the CRC Handbook for Chemistry and ...
4
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1answer
126 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 ...
7
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2answers
1k 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 ...
2
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2answers
40 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 ...
0
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1answer
50 views

Buffer action of borax

How does a mixture of borax and boric acid act as an acidic buffer? Please also describe the mechanism of its buffer action.
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0answers
31 views

pH of calcium carbonate in ammonium chloride solution (theoretical; not a calculation question)

Consider calcium carbonate saturated in 1.0 M ammonium chloride solution. I have calculated the pH of this solution analytically (with mass and charge balance) to be 6.92. Now, how would the actual ...
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1answer
24 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
48 views

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 ...
3
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3answers
56 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 ...
2
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1answer
35 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 ...
0
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2answers
27 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 ...
0
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1answer
32 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
83 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 ...
4
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1answer
32 views

Determining redox half-reactions of single displacement reactions

For the following double displacement half reaction, the half reactions can be determined easily using the oxidation numbers. $$\ce{MnO_{4(aq)}^{-} + IO_{3(aq)}^- -> MnO_{2(s)} + IO_{4(aq)}^-}$$ We ...
4
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1answer
120 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 ...
0
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2answers
57 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 $K_{sp}$ of $\ce{PbS}$. My Approach This ...
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0answers
18 views

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
30 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?
3
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1answer
65 views

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 ...
0
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1answer
63 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. ($K_a$ of $\ce{HCOOH}$ $= 10^{–4}$) My try: The number of the moles involved ...
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1answer
28 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 ...
2
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2answers
25 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 ...
3
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2answers
78 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
31 views

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

Is it possible to predict a double displacement reaction between two ions in aqueous solution? I see how you can predict precipitation reactions if you know whether the product(s) is solluble, but ...
6
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1answer
165 views

Acid-base equilibrium of NH4CN

I'm having difficulties understanding this problem. We have in the problem that $K_a$ for $\ce{HCN} = 6.2\cdot10^{-10}$ and $K_b$ for $\ce{NH3} = 1.8\cdot10^{-5}$. Write chemical equations to ...
5
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1answer
118 views

Byproducts of the neutralisation of hydrochloric acid with sodium hydroxide

Given a 1M 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
63 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 ...
2
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2answers
31 views

Find the color of the solution

The acid-base indicator methyl red has a $K_{a}$ = $1 \times 10^{-5}$. Its acidic form is red while its alkaline form is yellow. If methyl red is added in a colorless solution with a $pH = 7$, the ...
2
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3answers
36 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.
2
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1answer
76 views

Neutralization reaction

Question) Complete and balance each of the following molecular equations (in aqueous solution); include phase labels. Then, for each, write the net ionic equation. (A) $\ce{NH_3 + HNO_3 ->}$ My ...
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2answers
398 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
23 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 ...
2
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1answer
56 views

Is there a database which give reaction constant?

For instance, I have a chemical reaction like : $$\ce{Fe^{2+} + $0.5$O2 + H^{+} ->Fe^{3+} + $0.5$ H2O}$$ And I would like to use Action-Mass law, but I need to have equilibrium constant for this ...
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2answers
49 views

Reconciling the units of pH calculation

As part of a simulation I am developing I have an acid in aqueous solution represented as a concentration field of mass density (units g/L) at various points in ...
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3answers
68 views

Why does an acid exist when dissolved in water?

Acid is a substance that releases $\ce{H+}$ ions when mixed with water But if it releases $\ce{H+}$ ions the acid will ultimately not exist. For e.g we take the acid $\ce{H2SO4}$. If we add water ...
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3answers
121 views

Why are solutions electrically neutral?

I keep reading that solutions are electrically neutral, but I've never read an explanation. I've read after the fact justifications, such as one problem which asked me to calculate the force of ...
3
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1answer
62 views

In a redox reaction, why does more than one oxidation state of an element form?

Consider the reaction 100ml 10M $\ce{NaOH_{(aq)}} +$ 100ml 10M $\ce{NaHSO3_{(aq)} +}$ 100mL 0.01M $\ce{KMnO4_{(aq)}}$ In the picture posted here, the left columns give information on the Molarity of ...
2
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1answer
263 views

Solubility of p-nitrophenol in various substances?

So I had an organic chemistry lab where we had to dissolve p-nitrophenol in water, dilute $\ce{NaHCO3}$, dilute $\ce{NaOH}$, and dilute $\ce{HCl}$ to test for solubility. The p-nitrophenol dissolved ...
4
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2answers
199 views

Do buffers only work for species of the opposite variety? (I.e. weak acids buffer strong bases and vice versa)

I have looked at several sources including Khan Academy, ChemCollective and the answer to a similar question: Can someone please explain buffers to me? However, it is not clear whether buffers can ...
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1answer
207 views

How much carbonation is in one liter of commercial fountain coke-cola

From what I understand generally coke is carbonated to roughly 6.2g per liter in bottles and cans, or 3.1 volumes of CO2. I was watching this video because I was curious about how fountain soda ...
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3answers
85 views

Why is a buffer solution most effective when concentrations of salt and acid are the same?

Why does a buffer work most effectively when the concentration of salt and acid is 1:1?
2
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1answer
54 views

Permanent suspension of cocoa powder into water

I have failed in permanently suspending cocoa powder into water. I have tried heat (212'f) and pressure (40 psi) into a sugar water solution (50/50). Also, powdered milk and evaporated milk have ...
1
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0answers
92 views

How to break down soap and detergents?

I am building a greywater harvesting system. I have all of it designed except one aspect. It is a 3 phase system. The first phase breaks down soap and detergents. The second phase filters the water. ...
3
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1answer
79 views

Accuracy of pH meters in MgSO4 solution

I bought a 2 pH meters several months back from Amazon for roughly $10 a piece. I couldn't tell you how they work, but here's the link on Amazon: ...
3
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2answers
73 views

What is the minimum pressure for existence of a liquid solution?

The minimum pressure for the existence of liquid solution is $0.6\;\mathrm{atm}$ $0.8\;\mathrm{atm}$ $0.77\;\mathrm{atm}$ $0.9\;\mathrm{atm}$ Although this seems to be an informative question, I ...
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1answer
180 views

How do non-ionic compounds dissolve into water? Into molecules or atoms?

I can't seem to find the answer in google, which is surprising. I'm aware that ionic compounds dissolve into electrolytes. However, when non-ionic sacarose for example dissolves in water, does the ...
9
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2answers
121 views

Why doesn't the boiling point of an aqueous solution depend on intermolecular attraction?

I understand that boiling point is a colligative property for aqueous solutions, and that it empirically depends on the mole fraction of the solute, rather than the identity of the solute. I ...
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0answers
869 views

Temperature changes when salts dissolve in water

Please help me! I got this as an assessed investigation question and I really do not know where to start, or how I going to conduct this investigation. I understand that I should include information ...
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2answers
62 views

Stability of transition metals in aqueous solution

Which is more stable in aqueous solution $\ce{Cr^{3+}}$ or $\ce{Mn^{3+}}$? And why? My approach: $\ce{Cr^{3+}}$ should be more stable as the 3d electrons will enter the $t_{2g}$ orbitals. Due to CFSE ...