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

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2
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2answers
20 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
votes
3answers
28 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
67 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 ...
7
votes
2answers
289 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 ...
1
vote
0answers
10 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
votes
1answer
26 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 ...
1
vote
2answers
39 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 ...
1
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3answers
59 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 ...
1
vote
1answer
61 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 ...
1
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0answers
25 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
votes
1answer
73 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
votes
2answers
187 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 ...
0
votes
1answer
46 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 ...
1
vote
3answers
67 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
votes
1answer
34 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
vote
0answers
51 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
votes
1answer
44 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
votes
2answers
72 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 ...
1
vote
1answer
60 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
votes
2answers
111 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 ...
0
votes
0answers
348 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 ...
1
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2answers
53 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 ...
3
votes
1answer
45 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 ...
1
vote
2answers
99 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 ...
5
votes
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 ...
0
votes
0answers
48 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.
0
votes
1answer
36 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, ...
0
votes
2answers
62 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?
0
votes
1answer
69 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 ...
1
vote
2answers
348 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 ...
3
votes
2answers
114 views

Heat when dissolving solutes in water

Why do certain solutes dissolved in water release heat and other solutes absorb heat?
1
vote
2answers
137 views

How to dissolve steel without affecting aluminium alloy

Disclaimer: I have very limited knowledge of chemistry My problem is the following: I have motorcycle part made from some sort of Aluminium alloy - most probably 6005, 6061-T6 or 7005. And inside of ...
1
vote
2answers
26 views

Does removing solution affect a supersaturated solution

Given a mixture of: a saturated solution of a solute in a solvent together with excess of the solute compound as crystalline material. If one were to change the bulk composition of the mixture by ...
1
vote
1answer
36 views

Evaporation of a mixture of salts

I was wondering what happens when you boil dry a solution of several salts for example a solution of KCl and NaNO3. Since the ions dissociate I was wondering if the ions would combine randomly upon ...
0
votes
1answer
51 views

How much water has boiled off when precipitation begins?

Here's a challenge problem I created! None of my students could get it; can you? $25$ grams of table salt (NaCl) is dissolved in $150$ grams of water. The temperature of the solution is raised to its ...
4
votes
1answer
212 views

What is a complete reaction?

For a lab assignment, I combined 10mL of 1M sodium sulfate solution with 10mL of 1M calcium chloride solution. The ionic equation I came up with is: $$\ce{2Na^+ (aq) + SO4^2- (aq) + Ca^2+ (aq) + ...
1
vote
1answer
36 views

Two chemistry inquiries

Here is my second question, I know 1000 grams of water is 1 liter. But does the density affect the result? What if the substance is mercury? When you add seed crystal in to a supersaturated solution, ...
3
votes
2answers
107 views

Problems with precipitation of transition metal solution

I am trying to make a solution of "trace elements"--primarily transition metals-- for use in biological media; bacteria require elements like Cobalt, Molybdenum, iron, etc. in trace amounts. I am not ...
6
votes
1answer
91 views

How is an aqueous Ag+ the same as [Ag(H2O)2]+?

$\ce{Ag^{+}_{(aq)}}$ can be written as $\ce{[Ag(H2O)2]+}$ but how would you know that it bonds with 2 water molecules? I don't get when ligands randomly form 6, 4, 2 bonds.
0
votes
1answer
62 views

How do ligands and coordination complexes work in this case with copper (II) chloride?

What happens when Ammonia is added to an (aq) solution of copper II chloride? $\ce{CuCl2 + NH3 ->\; ?}$ I know that ligands bond with metals to form ion but I'm not sure about how they work in a ...
3
votes
1answer
53 views

Does supersaturated caffeine polymerize?

I tried preparing a supersaturated solution of caffeine by mixing anhydrous caffeine powder with water in a thin Turkish tea glass and heating it up over a candle (desperate times...). This worked ...
3
votes
1answer
94 views

existence and stability of Bifluoride ion

Consider the following homework question:- Statement 1. The $\ce{HF2^-}$ ions exist in solid state and also in liquid state but not in aqueous state. Statement 2. The magnitude of ...
2
votes
1answer
61 views

Solution containing Iodine

The question is:- Iodine dissolves in a variety of solvents forming solutions that are purple, brown or any intermediate shade. This property is due to:- Hydrolysis of iodine ...
2
votes
2answers
156 views

Are refractive or density based Brix meters better for use with alcoholic drinks?

Assume that somebody wants to measure the sugar content of a liqueur. It seems that there are two types of Brix meters for it, ones which use the solution density and ones which use refraction of ...
1
vote
1answer
108 views

Calculating approximate pH of polyprotic acids

When I took up ionic equilibria and titrations after a long break, I found it hard to solve the questions regarding pH calculations of polyprotic acds. Consider these two questions as examples:- ...
1
vote
2answers
313 views

Can two precipitates form in a precipitation reaction that starts with only two compounds in water? [closed]

I was wondering if two solids can form from two aqueous solutions? Any examples?
2
votes
1answer
223 views

What is the process of turning ionic silver solution into coloidial silver solution? (and some other related questions)

I've looked at a number of different colloidal/ionic "silver solution generators." After my research I'm under a few impressions and if they're wrong please let me know. I also am wondering what ...
3
votes
1answer
95 views

Could micrograms of polonium really change the viscosity of a whole teapot?

I was reading How radioactive poison became the assassin’s weapon of choice and it opens describing how The men eventually left, and Andrade cleared the table. As he poured the remaining tea away, ...
2
votes
1answer
116 views

Decomposition of iron (III) acetate?

I recently asked about the synthesis of iron (III) acetate. I want a rather concentrated solution to use as a calligraphy ink (which will be dissolved in alcohol/water). Will it be okay to heat the ...
4
votes
1answer
180 views

Can I synthesize iron acetate like this?

The oxidation state of the iron doesn't matter too much; I am just trying to make an attractive red-brown ink. Here are some instructions I prescribed to a friend. Here's an approximately decent ...