Questions tagged [aqueous-solution]
For questions relating to compounds dissolved in water and resulting reactions and acid-base equilibria.
939
questions
0
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4answers
75 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 ...
1
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1answer
51 views
Using solubility product to determine the mass of the precipitate of a reaction
I mix together $\pu{100 mL}$ of an aqueous $\ce{NaCl}$ solution at $\pu{0.5 M}$ and $\pu{100 mL}$ of an aqueous $\ce{AgNO3}$ solution at $\pu{0.3 M}$. Assuming that the solubility of $\ce{NaCl}$ in ...
1
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0answers
61 views
Is there a reason why we add (CH3CSNH2) but not H2S in qualitative group analysis? [closed]
Brief question: In $\ce{Cu}$-$\ce{As}$ group analysis we are expected to add thinoacetamide to make a precipitate with sulfide. Can we use $\ce{H2S}$ instead?
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2answers
61 views
How many Cl and Na atoms per Water molecule when salt dissolves? [closed]
When salt dissolves in water the Cl and Na ions or drawn to the polar water molecules.
Is it a one to one pairing? As in one Cl to the hydrogen side and one Na to the oxygen side?
2
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0answers
33 views
Which salts precipitate from a potassium/sodium chloride/sulfate solution?
This is not a homework question. I am not in any course of study. The following question arises from my personal curiosity. If 1 mole of sodium sulfate and 2 moles of potassium chloride are dissolved ...
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0answers
17 views
Explanation for difference in slope of graph of relative lowering of vapour pressure
Can someone tell the reason for the difference in the slope of graph of vapour pressure vs temperature of solid solvent and liquid solvent both the physical (actual process taking place) and ...
0
votes
2answers
67 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 ...
0
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1answer
44 views
Reactions of diborane, silane, methane, aluminium, boron, sodium, phosphorus trichloride, white phosphorus and iron with water at RT [closed]
How many of the following will evolve $\ce{H2}$ gas when dissolved in water under room conditions?
$\ce{B2H6},$ $\ce{SiH4},$ $\ce{CH4},$ $\ce{Al},$ $\ce{B},$ $\ce{Na},$ $\ce{PCl3},$ $\ce{P(white)}...
1
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1answer
102 views
Calculating the biological standard potential
I have an electrochemical cell with following overall reaction:
$$\ce{5 Sn^4+ + 2 Mn^2+ + 8 H2O <=> 5 Sn^2+ + 2 MnO4- + 16 H+}$$
I have defined the half reactions as:
$$
\begin{align}
\ce{Sn^...
3
votes
2answers
95 views
Diluting 4 % NaOCl to get a 1 % solution
Assuming that one has a 1 litre bottle of liquid bleach containing $4~\%$ sodium hypochlorite. If I wish to dilute it down to $1~\%$ sodium hypochlorite (to use as disinfectant), would adding 3 litres ...
0
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0answers
27 views
How do ethanoate ions react with water?
In an exam question, we are asked why ethanoic acid forms a basic solution when reacted with sodium hydroxide:
$$\ce{CH3COOH(aq) + NaOH(aq) -> CH3COONa(aq) + H2O(l)}\quad K_\mathrm{a}(\ce{CH3COOH})...
1
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1answer
47 views
Creating a 10 ppb Lead Nitrate Solution
Iām trying to make a 10 ppb Lead Nitrate solution as part of a concentration calibration step for a Beer Lambertās Law experiment. I plan on performing a dilution in three steps. The calculations have ...
0
votes
1answer
65 views
Why is the solubility of calcium sulfate so low even though it is a salt? [duplicate]
What is the reason the solubility of calcium sulfate in water is so low? Compared to other salts like potassium sulfate (110 g/L) or calcium nitrate (1470 g/L) the solubility of calcium sulfate seems ...
1
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1answer
40 views
Measuring mole fraction in lab using Raoult's law
I was reading in my textbook of chemistry on the vapour pressure in liquid compounds, and came across a doubt regarding vapour pressure. If I have two liquids, one is A and another is B, and if I know ...
1
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0answers
29 views
Effect of charge density on electrolysis of dilute sulphuric acid
I am told that if electrolysis of dilute sulfuric acid is performed under high charge density, then the following reaction takes place at anode instead of evolving oxygen:
$$\ce{2 HSO4- -> H2S2O8 +...
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1answer
60 views
Why do azeotropes boil at constant temperature? [closed]
As given in the Wikipedia page,
An azeotrope (/ÉĖziĖÉĖtroŹp/) or a constant boiling point mixture is a mixture of two or more liquids whose proportions cannot be altered or changed by simple ...
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2answers
38 views
In a double displacement reaction, why donāt the two products reform after being dissolved in water? [duplicate]
Letās say I have $\ce{AB (aq) + CD (aq) ā> AD + CB}$. When AB and CD are dissolved in water, they get dissociated into their component ions. But why donāt they reform as AB and CD, if it is already ...
1
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0answers
37 views
Two salts in mutual saturation, which one will precipitate first? [closed]
Let's say I have a satuated solution of two salts with a common ion e.g. KCl and KI, and they're at mutual saturation (let's say there are 75% by weight KCl/ 25% KI). If I slowly evaporate some water, ...
-1
votes
1answer
23 views
Difference between homogeneous and heterogeneous mixture [closed]
When i mix two equal but large number of stones it is possible (though extremely unlikely) that stone a and stone b perfectly segregate themselves into two halves or that they are uniformly ...
1
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1answer
35 views
Indirectly Measuring Diffusion of NO2 into Water
I am working on a data science project with the central hypothesis is that air-born pollutants can become water-born through diffusion. The example I am using as a proof of concept is $\ce{NO2}$. The ...
2
votes
2answers
92 views
Do all metal salts in aqueous solution contain metal aquo complexes?
I know that nickel nitrate in aqueous solution contains the metal aquo complex ion $\ce{[Ni(H2O)6]^2+}$. But do all metal salts in aqueous solution contain such complex ions? If not, on what factors ...
-1
votes
1answer
27 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 ...
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1answer
42 views
Microscopic View of Adding Water to A Basic Solution
I confronted a problem, stating that we have a solution of potassium hydroxide. By adding extra water, when the volume of solution reaches 630 mL, the pH decreases by 0.5 units. How much extra water ...
0
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0answers
27 views
Can the ion that isn't preferentially discharged discharge at the same time during electrolysis?
I would like to ask if the ion that isn't preferentially discharged can discharge at the same time during electrolysis.
Also, is the ion discharged at a much smaller extent or just discharged right ...
5
votes
2answers
357 views
Is the salt of a weak acid and a weak base also a weak electrolyte?
I'm able to find a lot of information on acids and bases, as well as strong-strong, weak-strong, and strong-weak salts. However all the introductory materials on electrolytes just stop there and say "...
1
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3answers
86 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) ā NH4+(aq) + OH ā(aq)
Will Fe(NO3)3 decrease the ...
0
votes
1answer
15 views
Is the specific heat of salt the same as Na + CL when dissolved? [closed]
I had this question when my friends were discussing how salt influences boiling time. When crystal salt is dissolved into water, it turns into a single Na and a single Cl atom. If knew the total ...
1
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1answer
45 views
Finding the volume needed to make a new pH
In the titration of 20.00 mL of 0.500 M HCl by 0.500 M NaOH, calculate the volume of 0.500 M NaOH required to reach a pH of 2.0.
I have tried to change the 20.00 mL into the amount of substance (0.01 ...
0
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0answers
32 views
Measuring ions through color change during electrolysis
I have very little experience in chemistry, you might consider me a physicist, and I am mostly not even sure where to find the information I need. I will start off by describing my problem, I have a ...
1
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0answers
26 views
Science of soap bubbles
On the web there are tons of different recipes for a solution to make soap bubbles.
Most of them use only three ingredients:
water
dish soap
glycerin
But their ratios widely change among the sources....
0
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0answers
45 views
Are these two reactions the same? [duplicate]
I read the book an it said when $\ce{NH4Cl}$ dissolves in the water, the reaction of $\ce{NH4+}$ will be
$$\ce{NH4+ <=> NH3 + H+},$$
but instead, the first reaction came to my mind was
$$\ce{...
0
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0answers
43 views
Is there an exothermic reaction when washing hands with water and hand sanitiser?
I accidentally washed my hands with water (cold/lukewarm) and hand sanitiser alcohol (room temperature) instead of soap. I felt like my hands have gotten warmer when I applied it.
Only using alcohol ...
0
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1answer
12 views
Creating 1L of 1000 ppb stock solution of Pb2+
Iām testing on samples that require a concentration of 1000 ppb (or 1 mg/L) of Pb 2+. My first thought was to simply dissolve 1 mg of Lead nitrate in 1 L of deionized distilled water to create 1 L of ...
0
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1answer
29 views
Basic Water Dissolving Salt Questions
I have a basic question about how water dissolves salt. In the Khan Academy explanation, it says that the H and Cl atoms attract each other while the O and Na atoms attract each other.
My question: ...
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0answers
15 views
What is the precipitate of aqueous copper (II) and polysulfides?
So if you heat up a piece of sodium engulfed in a large excess of sulfur, what you would get (from what I've read) is sodium polysulfide $\ce{NaS_n}$. But how large can $n$ get? If you left sodium ...
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votes
2answers
32 views
How does one dilute sulphuric acid (1.28sg@25ºc 460g/L) to 3 M Sulphuric Acid?
Thanks for looking.
The extent of my research around the issue so far.
SA sg table but wrong temp 60f not 77f/25c
http://www.sschemical.com/wp-content/uploads/2013/05/Conversion_Table.pdf
From
...
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3answers
37 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 ...
2
votes
1answer
24 views
Can o-phenanthroline be used as a complexing agent for lead(II)?
Iāve been trying to find a method to perform a spectrophotometric analysis to determine lead concentration (on the ppm level). This would require some chelator capable of forming a coloured complex ...
0
votes
1answer
26 views
Seeing solubility in various cases
[![enter image description here][1]][1]
Question is in the image 'match' each option having multiple answers. I have invested a considerable time over this but couldn't solve it. Anyone explaining how ...
2
votes
2answers
56 views
Chemicals that form coloured complexes with Pb2+
Iām currently conducting a photo-spectrometric analysis of lead concentration in water and was looking into using Eriochrome Black t as an indicator for Pb2+ (due to the complex forming a reddish ...
3
votes
1answer
285 views
How can I measure the amount of quinine in a home-made tonic water?
I'm into mixology, and lately I've been looking into experimenting with home-made tonic water, by extracting quinine (quinine salts) from cinchona barks in an acidic aqueous solution. I've read a bit ...
0
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1answer
29 views
Solution for Electroplating Selenium?
I need to electroplate selenium onto a conductive metal (for an experiment). The end goal is a thin film of pure, elemental selenium. Unfortunately I can't find anything on the internet: Ideally, I'd ...
0
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3answers
81 views
Is it possible to measure light absorbance for analysis of lead concentration without photospectrophotmeter
Iām designing an experiment which requires I measure final and initial lead concentrations for the determination of aqueous lead uptake by different mediums. Because lead concentrations would be ...
0
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0answers
45 views
What is the lattice enthalpy of zinc chloride?
I am trying to find a literature value for the enthalpy of solution of zinc chloride to compare with my experimental value but I can't seem to find it. So I'm trying to use the formula: enthalpy of ...
2
votes
1answer
29 views
How concentrated does the analyte solution need to be in order to perform a (chelatometric) titration
Iām currently investigating a method to chemically pretreat cellulosic waste as bisorbents for enhanced uptake of lead in water. I intend to measure the initial and final concentration of water to ...
-3
votes
1answer
69 views
aqueous solution recipe calculations: Using oxy-bleach as surface sanitizer [NOT A PERSONAL HEALTH QUESTION] [closed]
NOTE: Please do not delete this question. It is not a personal health question. The question has broad utility, in cases where others find themselves in social-distancing or quarantine with need for ...
0
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1answer
40 views
Mechanistic explanation of salt lowering temperature of ice slush
As we all know, adding salt to ice water lowers its temperature.
I've read plenty of system-level accounts of energy balances, enthalpies, vapor pressures, phase equilibria and freezing pointsāI ...
1
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2answers
84 views
Indicators of Cu(I) or Cu(II)
We performed an experiment in class where we placed a piece of copper wire in a solution of silver nitrate, we were tasked with predicted the mass of copper that should react and the mass of silver ...
2
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0answers
37 views
Hydrochloric acid substitute in an Iron-gall ink solution
Recently I started experimenting with making my own ink to be used in fountain pens.
I was wondering if hydrochloric acid in an iron-gall ink is used to prevent sediment ONLY by lowering the pH of ...
0
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1answer
24 views
Does PEO particle size decrease when dissolved in water?
I am looking to make metallic ink for inkjet printing and using PEO 1 wt% (MW ~600,000) as a binder. The print head I am hoping to use has a nozzle diameter of 80 microns. The metal powder dispersed ...
