For questions relating to water (H2O), specifically its structure, properties, and uses in chemistry.

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3
votes
1answer
287 views

Can a reverse osmosis system remove radioactive elements in contaminated water?

I am curious to know if a reverse osmosis system can clean water from radioactive elements like cesium-134 and cesium-137. If it can, how efficient can it be?
0
votes
1answer
21 views

Reduced-pressure (vacuum) evaporation/drying of 15 liters of aqueous solution

I have 15 liters of aqueous solution inside an aluminum stock pot which rests upon a hot plate. I want to reduce the boiling point from 150°C to 100°C using reduced pressure. What is the most ...
0
votes
1answer
26 views

Why some cloths become rough after drying?

I line dry my cloths and every now, they become rough after drying. This mostly happens with socks. They are regular cotton socks and once I start to wear them they become soft again. Any idea why ...
7
votes
1answer
317 views

What makes oceanic desalination so expensive?

What specifically makes oceanic desalination so expensive?
1
vote
0answers
25 views

Can Electrolysis be used to produce -OH

Water that is broken apart with electrolysis, will produce: Two atoms of hydrogen, which bond together to make di-hydrogen ($\ce{H2}$) or ($\ce{H-H}$) 1 atom of oxygen, or monatomic oxygen ...
-1
votes
0answers
24 views

The enthalpy of water molecule (distilled water)

Is the enthalpy of water less than that for individual hydrogen and oxygen molecules? And is the bond energy of distilled water sufficient enough to be used as a fuel in vehicles if the bonds are ...
1
vote
1answer
26 views

Electrons jumping from 1 water molecule to another

Electrons can be anywhere in the universe and where they are is random. But they are still discrete particles and thus it takes energy for electrons to move. Is it possible for an electron to jump ...
1
vote
1answer
12 views

Nitrates in water

In my previous question, someones answer among other things, said that boiling the water increases the concentration of nitrates and nitrites. I searched on google and it's true, but how does that ...
-2
votes
0answers
68 views

Wine/water mixing problem

The Water/Wine Problem is a classic logic problem that likely originated in the 1800s and was first published in 1896. The problem is usually stated something like this: Suppose your have two ...
4
votes
0answers
47 views

Why ginger reacts with sparkling water?

I think that the ginger ale is born this way. Anyway, if you put the ginger in a glass and add sparkling water, small drops splash out of the glass, the water is fizzier, more effervescent. Why? ...
1
vote
0answers
10 views

Trend in results for reproducibility of iron and phosphate

Periodically in our lab, we have a reproducibility test for the various samples that we analyze. One such sample is boiler water. Two of the parameters that we test are phosphate in boiler water and ...
10
votes
3answers
1k views

Why is condensation in dyed beverages colorless?

Does food coloring somehow evaporate and turn into nothing? Or does the beverage itself being much more color intensive? I had a bottle of Gatorade, colored Lemon-Lime (and flavored as such). I ...
9
votes
3answers
590 views

How is dissolving a physical change and not a chemical change?

When salt dissolves in water it dissociates and it is no longer in a lattice structure. The electrostatic forces are no longer there and are replaced by water-ion interactions. To me that sounds like ...
3
votes
1answer
38 views

Plastic membrane that lets water in from the outside only?

I'm looking for a type of plastic membrane that would let water through it from the outside, but wouldn't allow water to escape once it's inside the membrane. Ideally available in a roll. Does such ...
-1
votes
1answer
26 views

Energy required to electrolyze water [closed]

What voltage DC current would I need to electrolyze 1 liter of water in 1 hour using 1 gram $\ce{NaOH}$ for a electrolyte
5
votes
1answer
130 views

Aluminium and water safety

I have a 8000 gallon water tank that has always had pristine clear water. I have a brass float valve at the top input to the tank. Someone put an aluminum ladder in the tank (15 ft deep tank) and ...
4
votes
1answer
55 views

Is there a type of detergent/surfactant that evaporates at STP?

Are there any type of detergent/surfactant chemicals that would be good for removing dirt and grease from fabric that also would evaporate from the clothes within, say, 24 hours leaving no residue?
3
votes
0answers
29 views

Is there a food-safe hydrophobic liquid with a substanially higher denisty than water?

Requirements In short, I am looking for a fluid that meets these criteria: Hydrophobic Denser than water Low viscosity Food safe Background We are working on adding a pool and designing a ...
2
votes
0answers
53 views

What is that process called in which we add water molecules to an ion to form a complex?

An example would be $\ce{[Fe(H2O)6]^2+}$ in which it has 6 water molecules associated with it. What is the process of adding these water molecules called?
6
votes
2answers
167 views

Why there is no change in water level when salt is added?

Let us say we have one glass of water and after that when we add one or two spoon of salt then we notice that salt dissolves in it but when we measure the water level we found that there is no ...
2
votes
1answer
65 views

Quality of water for drinking purposes

As I’m reading about water cations and anions, I read that the benefits we gain from water are of course lots, but the most important of them is the neutralisation of acids ($\ce{H+}$) from the anions ...
1
vote
0answers
39 views

Why are H2O asymmetric while CO2 is not? [duplicate]

What is the reason for water molecules $\ce{H_2O}$ being asymmetric while other molecules like $\ce{CO_2}$ being completely symmetric? See the pictures below: In both case there is an ...
2
votes
1answer
44 views

how to define proper ppm concentrations for water solvent vs alcohol solvents?

1 ppm is 1 mg / kg Water density: 999.97 kg/m³ methanol density: 791.80 kg/m³ solution 1 with water as solvent: at 1 $\ce{\mu}$g / mL is considered 1 ppm solution 2 with methanol as solvent: at 1 ...
2
votes
1answer
51 views

Solubility and Evaporation - Would the concentration still be 1 ppm?

A certain salt has a solubility of 1 mg/1 L. I have 1 mg of this certain salt dissolving in 1 L of water, I have a concentration of 1 ppm. 1st Question: If the solution is left open to evaporation, ...
3
votes
0answers
22 views

how to clean pesticide solutions in volumetric glass and graduated cylinder properly?

I have pesticide (Dimethoate) dissolved in methanol in volumetric flasks and graduated cylinders. How do I clean these glassware properly before moving on to the next dilution of a different pesticide ...
-1
votes
1answer
55 views

Final concentration … How to calculate it? [closed]

My question is here but i just want to find out how to go about it? If 50.0 mg of $\ce{CO3^2-}$ and 50.0 mg of $\ce{Ca^{2+}}$ are present in 1 liter of water, what will be the final ...
2
votes
2answers
44 views

What is the difference between these equations for the Contact process?

Some webpages describe the contact process as this (I left out $\ce{SO2}$, $\ce{SO3}$ production): $\ce{SO3 + H2SO4 -> H2S2O7}$ After this, it is controllable to add water to the oleum therefore ...
0
votes
1answer
60 views

Cleaning an overhead water tank using Alum or other chemicals?

Alum is generally used in water tanks to settle down solid impurities. Since it contains aluminium I suspect it to be toxic to humans. So are there any safe chemicals to clean large overhead tanks ...
0
votes
0answers
22 views

How the heat a large amount of water that is safe to use?

I would like to know how heat up a large amount of water ( assumption : 100 liter ) that people could use to take their bath and also it would not be dangerous even if they accidentally ingested it ? ...
2
votes
0answers
37 views

The Health Effects of Alkaline Ionized Water?

I came across alkaline ionized water as my aunts bought a system called Kangen Water from Enagic Inc. The water produced by this system is claimed to contain smaller water clusters (4-6 molecules) ...
1
vote
0answers
29 views

Sugar dissolution test

Is there a way to detect whether sugar is completely dissolved in a cup of water other than looking at the bottom of the cup? I was wondering if there is a test or something that can be carried out ...
4
votes
1answer
94 views

Difference between Superheated steam and Superheated water?

I'm working on a project (school level) and in it I'll be dealing with the pressure generated by water when superheated. I could understand the concept of superheated water but superheated steam is ...
5
votes
1answer
335 views

What happens if I make a hole in a container with superheated water?

Superheated water is achieved by heating water above 100 degree Celsius under high pressure. Now, suppose the temperature at which the water is getting heated is around 250 Celsius and sufficient ...
4
votes
1answer
59 views

Water reacts or doesn't react?

I know that when you have $\ce{HCl}$, $\ce{H2O}$, and $\ce{NaOH}$ that you produce $\ce{H2O}$ and $\ce{NaCl}$. However some people say water does react and so would think that this 2 step reaction is ...
1
vote
1answer
59 views

De-ionized water [duplicate]

Is de-ionized water more corrosive to metals than tap water? I have read that it "wants" the removed ions back and will aggressively take them from any available source.
4
votes
1answer
39 views

Why are the three most simple alcohols completely miscible?

I want to know why the three most simple alcohols (methanol, ethanol and propanol) are completely miscible in water? I want to know what happens at molecular level. I think hydrogen bonding plays ...
16
votes
1answer
854 views

Are there any known chemical properties of tritium water that make it unusually different from protium water?

I suppose the first question supporting the main question is, has tritium water ever been synthesized in sufficient quantity to test chemical properties? If so, and apart from the obvious radioactive ...
5
votes
1answer
134 views

Vaporized sodium hydroxide?

Some time ago, I was making a $\ce{NaOH}$ solution. The solution I had made was much too concentrated, and the heat released in the dissolution of the ions caused the water to begin steaming. ...
27
votes
3answers
2k views

Why is fresh ice sticky?

Fresh ice cubes are almost instantly sticky and easily cling on to fabric and other similarly rough surfaces. A few minutes later, however, the effect almost completely disappears. What is the ...
5
votes
1answer
52 views

Why sodium sulphate has water absorbing capability?

At first I thought maybe sodium sulphate in contact with water produces sulphuric acid which absorbs water but I do not think it is actually a valid reason.
4
votes
1answer
49 views

Is there an electrolyte that will halt the production of Hydrogen in water electrolysis?

Care must be taken in choosing an electrolyte, since an anion from the electrolyte is in competition with the hydroxide ions to give up an electron. An electrolyte anion with less standard ...
2
votes
0answers
29 views

Reference request for the number of solvents around a solute

I want to know if there is a way to find number of solvent molecules that are directly embracing a solute molecule ( something like a reference or table that shows waters of hydration ). Particularly ...
5
votes
5answers
251 views

How can I calculate the charge distribution of a water molecule?

I would like to obtain the 3D charge density of a water molecule for plotting purposes (i.e. not necessarily super-accurate). I know this is a tough problem, but I'd like to give it a try. Since I'm ...
7
votes
3answers
1k views

Does salt vaporise?

Does salt vaporise? If I boil a salty water and leave it there until half of the water vaporises, will it be twice as salty as in the beginning? Or exactly the same? Or somewhere in between?
1
vote
1answer
24 views

Water softener and RO filter

I have a water softener for showers and dishwasher and a reverse osmosis filter for drinking water. For convenience of the install, the RO filter is using softened water (some calcium carbonate has ...
3
votes
0answers
56 views

theoretical model for the Hydrogen bond

I am curious how from the perspective of quantum chemistry the Hydrogen bond is modeled. In particular I am interested in using such a model to estimate the amount of energy released per $\ce{H2O}$ ...
3
votes
2answers
252 views

Can water be liquefied or solidified just by adjusting the temperature, regardless of the pressure?

technically the line between liquid and solid phase would go a long way before hitting the y-axis, but the point is it will eventually. So the question remains, can any liquids, including water ...
6
votes
2answers
184 views

Why is a tin can that appears like galvanised steel rusting?

I bought a canned pineapple and finished the content. The part of the can that is in contact with the liquid appears like galvanized steel (crystalline surface or spangles sort of appearance), while ...
0
votes
1answer
36 views

Which of these compounds does not liberate heat when water is added to it?

Which of these compounds does not liberate heat when water is added to it: $\ce{KNO_3}$, $\ce{NaOH}$, $\ce{CaO}$, $\ce{H_2SO_4}$, $\ce{Na}$. I know from experience that dropping sodium tablets into ...
3
votes
1answer
36 views

Chemical based Water Purifier

I am currently researching as too which is better for purifying a water sample. I have obviously tried the standard Google search for 'Aluminium Sulphate or Ferric Chloride' and have come up with lots ...