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For questions relating to water (H₂O), specifically its structure, properties, and uses in chemistry. For questions not about water but rather about solutions in water, use tags [aqueous-solution] or [solubility] instead.

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Converting Chlorine Dioxide concentration to Chlorine

Looking for a little guidance. I have been given some water quality data as part of a project. Specifically I'm interested in the concentration of Chlorine in river water. The analysis results ...
4
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1answer
54 views

What component(s) of instant coffee make it deliquescent?

If I put small, separate piles of instant black coffee powder, sugar, powdered creamer, and even something very ionic like table salt out in humid air and come back in a few days, only the instant ...
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0answers
19 views

How much H2 can I produce from water with a private home solar panel? [on hold]

I am a layman when it comes to chemistry, I only know what I learned in school which is quite some time ago, so forgive me if I get some terminology wrong. I was just informing myself about hydrogen, ...
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1answer
21 views

Basic Titration Question : Titrating weak acid with strong base [on hold]

I'm having trouble understanding the titration of a weak acid solution ($\pu{0.1M}\ \text{acetic acid}$) with a strong base ($\pu{0.1 M}\ \ce{NaOH}$). I know that there are two reversible equilibria ...
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1answer
34 views

Acids using different solvents [on hold]

Many polar protic solvents exist and ionic compounds are able to dissolve inside these substances for the same reason as water. So, theoretically, if a substance were to steal a $H^+$ ion from a polar ...
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0answers
26 views

Chemical test for water content in an epoxy-anhydride resin mixture

I am looking for an effective chemical test for determining the level of water content in an epoxy-anhydride mixture. We have a large amount of epoxy and anhydride curing agent that we need to test ...
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2answers
68 views

Can ideal gas law be applied to water vapour? [closed]

How to accurately estimate the molar concentration of pure water vapour at 298 K? Can ideal gas law be applied to water vapour to calculate the molar concentration?
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1answer
43 views

Is the relative humidity of pure water vapour 100%?

If there is pure water vapour in the gas phase, can the partial pressure be taken to be equal to the vapour pressure of water at that particular temperature? edit: How is relative humidity calculated ...
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0answers
19 views

Variable Conceptualisation in the Boiling of Water

I'm writing up an example report targeted for a year 7 science student audience. The report aims to "Determine the boiling point of water" in an open system. It aims to introduce a particle model of ...
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1answer
45 views

Diluting methanol in water: is it exothermic?

Can someone explain in simple terms why does temperature increase when mixing water with methanol? I do not have a strong background in chemistry, but I usually have to mix both liquids (sometimes ...
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1answer
54 views

Hygroscopic Substances and Drying Agents

My book says: Most of the hygroscopic substances are drying agents Based on what I read on several websites, I think dehydrating agents also act as drying agents. If so, all dehydrating agents ...
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0answers
36 views

does adding water to water release heat/increases temperature of water

Multiple sources as mentioned below says formation of bond releases energy including hydrogen bond .So i was wondering, as hydrogen bonding is present in water so when you add water with water would ...
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1answer
20 views

Mechanism of Water Potential

The idea of water potential still confuses me. I understand the general idea: water moves from an area of higher water potential to an area of lower water potential. However, I still do not understand ...
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1answer
54 views

Understanding water models?

I generally work on fluid flow, so some basic concepts in chemistry are new to me. Work I'm doing requires use of molecular dynamics (MD) to do classical potential simulations of water–NaCl systems ...
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1answer
27 views

Which chemical could be used to decrease water boiling point to a minimum possible level without heating it [closed]

I aim to decrease boiling point of water that will be used to generate steam. I wonder maybe there is an opportunity to add a substance that will help to decrease boiling point of water without ...
4
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1answer
93 views

How does chlorine in water evaporate?

Drinking water (e.g. from your home's tap) is spiked with chlorine, for an amount of just some ppm. Purpose of this operation is to kill bacteria, for our health. Background: chlorine in water is ...
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0answers
54 views

Reason for formation of bubbles at boiling point [duplicate]

As I understand it, boiling takes place when the saturated vapour pressure equals to the atmospheric pressure. But, why does the vapour pressure need to be equal to the atmospheric pressure for ...
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1answer
26 views

Will a container made of ice hold an alcoholic beverage that is below freezing in an environment that is also below freezing? [closed]

This very specific question that came after saw I a travel episode where they served alcoholic beverages in ice glasses in an ice bar. I wondered if the drink contents would stay in the glass (of ice) ...
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1answer
20 views

Removing water/moisture from car exhaust [closed]

I know that car exhaust is almost entirely nitrogen, water and carbon dioxide. How would I go about removing the water? Would I have to condense it off? Any devices already exist for doing so?
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1answer
840 views

Is there a compound that contains water as a subcomponent? [closed]

Is there a molecule that contains water chemically bonded to another molecule/element? Could someone provide an example or two?
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0answers
27 views

What happen if i keep etched silicon underwater?

I am trying to remove oxide of silicon by using etching solution. After etching, usually silicon turn shiny. But just out of curiosity i let it soak in water overnight, the surface of silicon is a bit ...
3
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1answer
492 views

Why is ammonia less acidic than terminal alkynes?

Here's a picture from Organic Chemistry by Solomons, Fryhle & Snyder : Why is it that ammonia is less acidic than terminal alkynes even though water, and even alcohols, are more acidic than them?...
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0answers
68 views

How to measure pH of deionized water

reverse osmosis deionized water (RODI) is used to rinse acid off silicon after it undergoes silicon etching. Sample of water is taken and measured by using pH meter. However, pH meter takes a 1-2 ...
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2answers
957 views

Why is creating water exothermic?

I have to calculate the bond dissociation energy of steam. I'm a total noob, so don't go too hard on me. (I'm translating the exercise by myself, sorry if there is a mistake.) Calculate the bond ...
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0answers
48 views

Why does IPA turn cloudy when added to water?

When I pour isopropyl alcohol into water (tap water not distilled water), it turns cloudy. I’ve heard that alcohol is miscible with water (the the liquids should not give a precipitate) . Also, what ...
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2answers
188 views

The effect of pH and solubility on coagulation in water treatment

In water treatment, a specific pH range must be met in order for the process of coagulation to occur properly. Sources have stated this is due to the pH affecting the solubility of the coagulant, but ...
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1answer
53 views

What is the solublity of water in liquid carbon dioxide at low temperature?

The solubility of water in liquid carbon dioxide has been investigated by Hosmer W. Stone in 1943 from -29 to about 22 °C. Is there any research done on the solubility of water in liquid $\ce{CO2}$ ...
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1answer
58 views

Can we manipulate the rate of water's autoionization?

I just got introduced to this concept and these thoughts came into my mind. Is there a way to increase the equilibrium constant of the autoionization of water?
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1answer
178 views

Is there a substance that hardens in water? [closed]

Im trying to invent a product that starts as a liquid but when exposed to water it hardens. Is there any chemicals that can cause this reaction??
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4answers
311 views

Why does the Leidenfrost effect (seemingly) not apply to the case of molten NaCl when it is poured into water?

On pouring molten sodium chloride into water you can see that when molten $\ce{NaCl}$ (table salt, i.e. sodium chloride) is poured into water ($\ce{H2O}$), the Leidenfrost effect appears to be ...
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1answer
55 views

How does the water pollutant sodium nitrate affect the concentrations of other ions in tap (dam) water? [closed]

Context In my assignment I've been given two water samples from the hinze dam. The first sample has been untouched, however the second has been contaminated with an unknown ionic compound. To ...
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2answers
68 views

How to find the mass of the following solution? [closed]

What is the weight of a 1L of 0.5M solution of NaCl? Is it the whole solution weight 29.22 grams?
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1answer
74 views

How can we say whether or not an organic compound is soluble? [closed]

In the exam recently conducted by my school, they asked whether 2-hydroxyacetophenone is water soluble or not. I thought that since there is intramolecular H-bonding in this compund, it won't be ...
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0answers
39 views

How do concentrations of nitrate in water samples change over time?

Context: (Not necessary to answer the question) For an assignment I am currently testing two samples of water. One is a pre-contamination sample and the other is a post-contaimnation sample. Between ...
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0answers
40 views

Is there anyway to derive the number of water molecules in a hydrated salt, given just the formula for the anhydrous salt?

Is there anyway to derive the number of water molecules in a hydrated salt, given just the formula for the anhydrous salt? That's pretty much it. If not, why? For coordinated water, my guess is ...
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2answers
51 views

Do we consider the dissociation of water when dealing with ion concentrations of a solution?

One mole of hydrated copper(II) sulphate, $\ce{CuSO4 . 5 H2O}$, is dissolved in water. How many moles of ions does the solution contain? 1) 1 2) 2 3) 6 4) 7 The ...
13
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1answer
2k views

Why does adding salt to boiling water cause it to flare up suddenly?

I was expecting that the water would become less "boily" since the ions in $\ce{NaCl}$ would require energy to disassociate. Instead it turned whitish and the water level suddenly rose and then ...
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0answers
27 views

What is the future of water treatment, and why we don't use enough purified sea and freshwater? [closed]

I understand thermal and membrane distillation are very expensive and that slowed down their usage, but now we can bring 100% clean energy to power them. Except the set-up, the price of materials and ...
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0answers
18 views

Different machines testing for same thing

For a chemistry report, we were given a sample of water and a variety of machines to test it with - giving their respective results about whatever aspect they were testing (eg pH, metal ion ...
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1answer
75 views

From where does sea water get salt?

I have learned that in primary classes that sea water is salty and I had also wondered that, what makes it salty? and my question is, where does sea water gets its salt?
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2answers
677 views

Does salinity affect seawater's pH?

If so, how? It seems like excessive salinity within seawater has the same destructive effect on marine organisms just like excessive acidity. But in real terms, is there any relation between salinity ...
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0answers
43 views

What's the density of a frozen ethanol or ethanol solutions?

How can we know what's the density of ice (water), but there's no data on how much is the density of frozen ethanol? (as far as I know)
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1answer
270 views

Is the relationship between Ka and Kb the same for all acid base pairs? [closed]

What is the relationship between $K_\mathrm{a}$ and $K_\mathrm{b}$ for acid/base reactions. I know for water $K_\mathrm{w}=K_\mathrm{a}\cdot K_\mathrm{b}$, where $K_\mathrm{w}$ is $10^{-14}$. Is this ...
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1answer
89 views

Why does the gas from dry ice flow down?

I am reading Dan Broughton's answer in replying to the question "why does the gas from dry ice flow down" here. According to the answer, the fog is water's color and water is condensed and suspended ...
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1answer
257 views

How thick is a snowflake?

The x, y dimensions of snowflakes get all the attention for obvious reasons, but the z dimension must be interesting too, in its own humble way. In fact, I have lived more than half a century and ...
5
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1answer
92 views

Number of water molecules in a box to simulate liquid water [closed]

I have seen that depending on the simulation approach, different number of water molecules are employed for studying liquid water properties. 32 in early DFT calculations The electronic structure of ...
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1answer
65 views

How to calculate mass of water of crystallisation?

How do you work out the mass of water of crystallisation for 13.5 g of $$\ce{Al2(SO4)3*6H2O}$$ The correct answer is 3.24 g of water but I'm unable to derive the answer. What I have tried: I ...
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0answers
25 views

How to make snow [closed]

I want to make a DIY snowgun. I wonder how is snow chemically made? What is the temperature needed? What is the pressure needed? What is the density of water to throw in the air? What is the humidity ...
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1answer
79 views

Why hot water freezes faster than cold water? [closed]

When we put cold water in the fridge it takes time to freeze but hot water is fast in freezing.Why?
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1answer
85 views

Definition of water Plasticization [closed]

Can someone explain what is water plasticization? I tried to look for the definition but could not find one that explains it.