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

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0answers
16 views

Salt concentration and electrical permittivity of water

We know that the electric flux density $D$ can be related to electric field intensity $E$ as $D=\epsilon(\omega) E$ $\epsilon(\omega) = \epsilon_0 \epsilon_r(\omega) $ where $\epsilon_0$ is the ...
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1answer
23 views

Approach to model solvent in a lattice: e.g. H2O in NaCl

If a lattice contains a solvent, lets say NaCl and water of crystallisation, what is the condition for a solvent molecule to change it's location? From my current point of view I assume that such a ...
3
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1answer
35 views

Electrolysis of Beer

Electrolysis of water, means that the water is separated into hydrogen and oxygen. As beer also includes water, I initially thought electrolysis of beer would cause the water to separate, and the ...
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1answer
25 views

Determination of chlorine in swimming pool water

How do I get started? What kind of experiment do I need to carry out? What equipment would I need for this experiment? Any other help/advice is appreciated.
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1answer
22 views

water vapor vs air (in a balloon)

I poured some water in a balloon, inflated, and tied it up. Over a period of couple weeks, all water in the balloon is gone. But the balloon is still at about 2/3 of original inflated size. I ...
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3answers
2k views

Would equal masses of gold and copper result in the same volume change if added to water?

Would equal masses of gold and copper result in the same volume change if added to water? Density of gold: $19.3~\mathrm{g/mL}$ Density of copper: $8.96~\mathrm{g/mL}$ I was thinking the ...
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1answer
40 views

What happens when ice melts?

What happens when ice melts? I have this question, with two possible answers: regularly arranged molecules change into irregularly arranged molecules water molecules become less densely packed ...
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0answers
18 views

Fluoride Color Reaction

I am trying to find visual ways to demonstrate water contaminants. For example, chlorine reacts to N,N-diethyl-p-phenyldiamine (DPD), forming a magenta color. The chemical doesn't need to be accurate, ...
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1answer
27 views

Effect of water viscosity (increased due to NaCl concentration) on dissolution rate of CO2

We did an experiment involving different $\ce{NaCl}$ concentration(ranging, 1-4%) on 100 mL of water. Our aim of the experiment was to find the dissolution rate of $\ce{CO2}$in the brine solvent. We ...
3
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1answer
583 views

How much oxygen is in a cup of water?

I know that water is 2 parts hydrogen and 1 part oxygen. Hydrogen and oxygen are quite light gasses, they don't weigh very much compared to water. Water is very heavy and it made me wonder exactly how ...
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0answers
14 views

Does CO2 dissolution in different salt concentrations affects the amount of carbonic acid formed?

We have a school experiment, where I must report on the following question: Does salinity affect the solubility of $\ce{CO2}$ in saltwater? So we selected four different concentrations of salt ...
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0answers
12 views

What additives could make a masonry unit water-repellent but vapor-permeable?

I'm curious about some of the wondrous materials available today are able to repel liquid water but permit water vapor to pass through. I've heard that housewrap-type plastics accomplish this by being ...
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2answers
44 views

Using Hydrates as a skin moisturizer

I was just in my AP Chemistry class earlier today learning about hydrates and their properties. It occurred to me that a compound with so much water could aid in moisturizing the skin. Is this a valid ...
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0answers
11 views

How to produce hot water-soluble soap balls? What is their chemical background? What about medical capsules?

There are water-soluble balls for soap baths. Then there are medical capsules that disappear in mouth. Is it possible do this kind of capsules and water-soluble containers at home? If not, what do I ...
4
votes
1answer
284 views

What is the bond angle of H2O?

I have been trying to find out the bond angle of H2O, but every site I visit has a different answer. So far, I have found the following angles listed: Site 1: 104.4º Site 2: 107.5º OR 104.5º, ...
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votes
2answers
199 views

How much does water expand when heated, and does salt affect that?

For this question, assume all things not mentioned are perfectly controlled, all at 14.7lbs of atmospheric pressure, and water is 100% pure of anything not mentioned, with no dissolved air. Given a ...
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1answer
64 views

Chlorination of Water

Does passing chlorine gas through water form hydrochloric acid or bleach? Also, will a mixture of hydrogen and chlorine gas from electrolysis of brine do the same?
3
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1answer
33 views

Reaction of distilled water with hard water

This question seems silly, but this just came in my mind while i was learning Hydrogen. Means will there be any reaction when $\ce{H2O}$will react with $\ce{D2O}$..
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0answers
21 views
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24 views

Analytically combining Dynamic Equilibria that have a two way affect?

Lets say I want to model a water system as the following set of equilibria: $\ce{H2O <=> OH- + H3O+}$ | $\ce{A=[OH^{-}][H3O+]}$ $\ce{CO2 + H2O <=> H2CO3}$ | ...
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1answer
39 views

How much water would one loose if one burns hydrogen and oxygen?

By using electrolysis one can separate hydrogen and oxygen, but when burning hydrogen and oxygen together steam is released, therefore creating water. My question is: how much of the original ...
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1answer
33 views

tap water and distilled water for electrolysis

my water electrolyzer which I've built using this pdf, produces less gas than I expected. In that file the author insists on using distilled water instead of tap water and I have used tap water. would ...
2
votes
1answer
385 views

How can I identify whether a substance is KOH or NaOH?

I've bought NaOH or KOH (I don't remember which one!) for my electrolyzer and I've tested it. Now I want to improve its performance and I was searching for a better electrolyte when I realized I've ...
0
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1answer
85 views

calculate the amount of energy in KJ necessary to convert 346 g of liquid water from 0 C to water vapor at 182 C

Calculate the amount of energy in $\mathrm{KJ}$ necessary to convert $346~\mathrm{g}$ of liquid water from $0~^\circ\mathrm{C}$ to water vapor at $182~^\circ\mathrm{C}$. The correct answer is ...
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2answers
58 views

Are non-ionic compounds generally as dehydrating as ionic compounds in drinking water?

In order to turn sea water into drinkable water, virtually all of the salt must be removed. By definition, salts are ionic compounds. I am assuming that there are other non-ionic compounds devolved ...
5
votes
1answer
91 views

What stable arrangements of hydrogen-bonded water exist in the range of 4-20 water molecules?

Water clusters made up of various numbers of water molecules have been described. Are all of these structures theoretical? What experimental evidence supports any of these structures? How does the ...
2
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1answer
19 views

High/low density water solution values

I would like to know what min and max values of densities are achievable with water solutions. There are some conditions: 1. Normal or close to normal temperature; 2. Non-radioactive ...
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votes
2answers
65 views

How can the density of water be maximised?

What is the maximum possible density of water at room temperature? The density of the water in the dead sea at 37 Celsius is 1.24. Would it be possible to increase density as such using salts we add ...
3
votes
1answer
45 views

Ethanol and water hygroscopic equilibrium concentration

I am working with a company to help improve their reaction process where they use SDA 2B Alcohol (Karl Fischer titration has it at 99.66% EtOH, 0.3375% toluene). Specifically, I am attempting to ...
2
votes
1answer
41 views

Can electrolyzing ice cause an explosion?

I know electrolyzing water separates it into hydrogen and oxygen. However, I am curious, if ice is electrolyzed, could it explode? My thought process is that oxygen and hydrogen bubbles would build ...
2
votes
2answers
77 views

Can water be produced by mixing hydrogen gas and oxygen?

Could there be some kind of process, a kind of "retrograde electrolysis" where hydrogen gas (or in some other form) and oxygen gas (or in some there form) are mixed with required energy to combine to ...
2
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1answer
83 views

Is there a readily available liquid that's more dense than water and insoluble?

I am looking for any liquid that does not dissolve in water with higher density and does not react with water, one that is readily available.
6
votes
1answer
275 views

Soap and rain water, why does it not rinse off?

I am in Papua New Guinea at the moment, where rain water harvesting is the most common way of getting water. When washing hands, the soap feels hard to rinse off, and my skin feels "greasy". I read ...
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0answers
21 views

What is electrodialysis and is electrolysis prevented or suppressed?

Recently, I was introduced to a method of desalinization called electrodialysis in which a current was applied to salt water in such a way that the positive and negative were separated and drawn ...
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1answer
42 views

Which acids are created by the combination of a gas and water?

Which acids are created by the combination of a gas and water? I know that carbonic acid is created by combining carbon dioxide and water, but are there others? Is there a specific name for this ...
0
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1answer
45 views

Solar still and how it works

I use a solar still that holds 182 cubic feet of water. Here is how it works: There is an insulator on both sides of the metal bowl. On the outside it covers the whole thing. on the inside it covers ...
0
votes
1answer
52 views

What are the methods of fluoride removal from drinking water?

I would like to remove fluoride from my water supply. Are there any methods, any test kits or water distillation units to remove fluoride from drinking water? See also: Is there any at home test ...
0
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1answer
37 views

How to test for fluoride levels in drinking water?

I would like to test for fluoride levels in the water. Are there any methods or test kits available to test the levels of fluoride in home water supply? See also: Is there any at home test for ...
5
votes
1answer
108 views

Rusting of an Iron nail at oil water boundary surface

Recently at school, I did some experiments on corrosion. Everything mostly went as expected, but the result in one of the test was quite baffling. This test had an iron nail in water with some of ...
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0answers
40 views

How to determine amount of CO₂ in soda water

I've got a problem in determining the amount of $\ce{CO2}$ in soda water. Basically, I have boiled some purified water to remove the dissolved gas. By using a SodaStream machine, I made carbonated ...
0
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1answer
48 views

Can I perform electrolysis without electrolyte? (with distilled water)

When performing electrolysis at home, I usually used salt water as electrolyte. The problem is, that this method also produces chlorine and chlorine is aggressive to both humans and electrical ...
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1answer
23 views

Double Deionized Water and Superheating

I was told that dd-water will superheat when heated up in a microwave because of a lack of ions. 1) Doesn't water auto-ionize? I asked this; the answer was it auto-ionizes "too slowly" in dd-water ...
4
votes
2answers
194 views

What is the reason for anomalous expansion of water?

What is the reason for anomalous expansion of water? Why don't it simply expands on heating or contract on cooling. Why it shows anomalous behavior at 4 degree centigrade? Why not on 4,6 or 10 (or ...
0
votes
1answer
30 views

Behaviour of water at exactly 0°C

If I had a beaker of water (i.e. many molecules), at exactly $0^{\circ}C$ and at atmospheric pressure, what phase would be encountered? And would the answer to this also apply to other substances at ...
0
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1answer
32 views

Hydrate questions

Two questions that I'm really stuck on: A sample of cobalt(II) nitrate hydrate was heated to remove all the water of hydration. The hydrate was found to be 65.96% oxygen. Calculate the number of ...
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0answers
39 views

Specific Heat of Water Solution

If we add an ionic solute to water, will the specific heat of the water be increased or decreased? I understand that the specific heat is a measure of how much energy we must add to water for the ...
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2answers
27 views

Water purification procedure that does not involve a flocculant of any kind?

I have read about "electroflocculation" that uses less flocculant/alum, but is there a method – no matter how expensive or impractical – that uses no flocculant at all?
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2answers
55 views

What's the Acid Ionization Constant of the Hydrogen Proton?

What is the $\ce{K_{a}}$ value for $\ce{H^+}$. I understand that the hydrogen proton doesn't stick around in solution by itself for very long. Nonetheless, does it have a $\ce{K_{a}}$ value? Can it ...
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3answers
3k views

Why doesn't a table sublimate, while ice does?

A table does not sublimate, and nor does a spoon. Ice does, however. What is the fundamental difference?
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0answers
78 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. ...