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

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34 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 ...
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3answers
45 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
18 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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2answers
25 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
22 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
55 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
26 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 ...
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1answer
105 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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2answers
49 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
17 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
26 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
52 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 ...
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1answer
42 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
26 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 ...
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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 ...
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2answers
68 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 ...
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1answer
107 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 ...
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1answer
103 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
53 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
29 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 ...
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3answers
35 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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1answer
74 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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329 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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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 ...
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1answer
41 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
43 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
66 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
101 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 ...
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1answer
55 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 ...
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1answer
134 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 ...
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2answers
193 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
87 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
75 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?
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1answer
45 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 ...
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0answers
76 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. ...
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1answer
63 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: ...
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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
100 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 ...
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2answers
114 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
536 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
58 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 ...
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1answer
49 views

metal salt solutions g/l means hydrate or anhydrous

I want to redo an experiment. They've used Nickel chloride: 40 g/L Nickel chloride can be bought in two forms: anhydrous ($\ce{NiCl2}$) and hydrate ...
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2answers
106 views

Is this a trick question?

Disclaimer: It has been a very long time since I have done any chemistry. My friend posted this question on social media, I've copy+pasted it here: Exactly 16.0ml of a solution A is diluted to ...
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1answer
1k views

How could alcohol be made into a powder?

In the news recently is 'Palcohol', powdered alcohol, http://www.palcohol.com/home.html that you add to water or existing liquids to make it alcohol. Presumably this would dissolve and break apart ...
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51 views

How can I carry out a titration to identify mercury in wastewater?

First, I would like to do a some form of extraction to only get the mercury, then followed by a titration to identify the concentration or the presence of mercury.
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65 views

Electrolysis of aqueous lead nitrate

When going through one of my chemistry textbooks, I saw that the electrolysis of aqueous lead nitrate led to oxygen being formed at the anode and lead being formed at the cathode. However, in school, ...
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2answers
64 views

HF and water miscible?

According to Wikipedia, HF is miscible with water. But isn't hydrogen fluoride a gas at RT and a sensible pressure? What would happen if you just kept adding more HF gas to some water?
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82 views

Zinc Picolinate - Positive, negative or neutral charge?

I'm going to be using a finings agent with a positive charge to remove negative trub from a solution (beer). I would like to keep some chelated zinc in the solution - ideally zinc picolinate - so ...
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2answers
675 views

How do I prepare a 5N HCl solution?

I am trying to make 5N $\ce{HCl}$ solution. So far I understood that you need to get the molecular weight (36.5) and divide it by the number of $\ce{H+}$ that react in the acid-base reactions. The ...