Solvent Definition and 80 Threads

The equilibrium constant is $$K=\frac{a_{\mathrm{H_3O^+}}a_{\mathrm{OH^-}}}{(a_{\mathrm{H_2O}})^2}$$ where ##a_J## denotes the activity of a solute ##\text{J}## in a dilute solution, ##\mathrm{[J]}/c^\circ## with ##c^\circ=1\mathrm{mol\cdot L^{-1}}##. The book I am following says that the...

I'm looking at berryman's b12 chemtool. It is used with success to remove carbon deposit on piston rings, breaking them free from sticky sludge, and thereby lessen oil consumption. I can not get the product where I live. So I wonder if I could copy the effect by identifying the most lightly...

Hello. I have an interest in aquiring a soxhlet extractor glassware kit for experimentation and learning. Something small like with a 250ml flask. Not sure what geometry of condenser to go for, Graham Allihn, straight or else. I will be using dichloromethane as a solvent and would like to...

Hello everybody , In my research study, i am focusing the interprete the effect of solvent on opticals propertie of carbazole based hole transporting materials ,In order to dissolve this materials in different Concentration of solvents ; I have been using Toluene , chlorobenzene and...

I know that in protic solvents I- is a strong nucleophile and F- is a poor nucleophile due to solvolysis. But why should I- become a poor nucleophile in an aprotic solvent and F- become a strong nucleophile in aprotic solvent? Why this reversal of nucleophilicity i.e., F->,Cl->,Br->,I-> ?

Homework Statement I need to find the distribution coefficients for acetic acid of various concentrations in a ether/water system, but I'm not too sure of my calculations Homework Equations To get the concentrations of acetic acid in the aqueous phase I took the ([average concentration of...

I'm a high schooler involved in a research in which we aim to grow perovskite crystals in microgravity. I've recently come across this article (https://scitechdaily.com/researchers-develop-a-better-method-for-making-perovskite-solar-cells/) in which they explain how to grow better perovskite...

The question I have been given: Draw the dominant forms of each of the compounds below and state which, if any, would be expected to extract from aqueous solution into hexane at (a) pH 12 and (b) pH 2. CH3CH2COOH CH3CH2NH2 CH3CH2CH2OH H2NCH2CH2COOH From my understanding, I can tell what the...

Things I have thought of till now: Acetonitrile with HI additive Acetonitrile with DMSO additive The problem with the first would be that HI is in an around 55% aqueous solution and water doesn't play well with the perovskite. Meanwhile, the second might end up needing enough DMSO to...

I have an aerosol based 'oven, and chimney cleaning' product. Here are the contents: Aqua Propylene Glycol Butane Ethanolamine Cocamide DEA Propane Sodium Hydroxide Sodium Laureth Sulfate Xanthan Gum Parfum From the list, it appears that the only active ingredient is Sodium Hydroxide...

Homework Statement 10g of CaFl2 is disolved in 100 grams of water, what is mass/mass concentration Homework Equations c = mass of solute/mass of solution The Attempt at a Solution Would it be 10/100 = 0.1 or 10/110 = 0.091

What home based solvent might dissolve an unknown electron microscope seen insoluble particles ? There are some sort of unknown insoluble particles in our water. Does anyone know of any home remedy acid solution (baking soda and vinegar) that might dissolve these particles ? Please keep in...

Most solvents we use in the laboratory have some shelf life. Experimental example: Say you have a 4L bottle of anhydrous toluene and you regularly pour out/use small volumes of it over the course of a year. One year from opening date, you have 1L of toluene left. Will this toluene still be...

I am currently studying nucleophilicity of molecules and am getting a set of conflicting information, so I wanted to clarify nucleophilicity trends with respect to solvent. The link below discusses how nucleophilicity increases down the periodic table with protic solvents and decreases down the...

Homework Statement I want to extract and quantify lipids inside the starch. Which solvents you recommend for the extraction? Homework EquationsThe Attempt at a Solution

People seem to use DCM (dichloromethane) for this, but I was wondering if trichlroroethylene would also work.

If nucleophile is ambident and solvent is polar aprotic, more electronegative atom is free to attack the substrate. Since more electronegative atom is a hard base, it forms a stronger bond with hard acids like carbocation. This promotes formation of carbocation by substrate. Hence, SN1 reaction...

Hey Everyone, I'm having trouble detecting my drug dissolved in ethanol using UV-Vis spectroscopy. The peak absorbance of the drug is at 240 nm while the peak absorbance of the ethanol seems to be around 190 nm. Are these peaks too close to each other to get an accurate measurement? In the...

When we drop a coffee droplet and wait for it to evaporate, there is a coffee ring left. Because there is coffee dissolved in the solution, and when water can evaporate into the air, the coffee cannot evaporate and it will stay. Therefore, if we drop one DI water droplet onto the substrate...

Hello, Can anyone recommend a good solvent for sodium bentonite? I have used it as a sealant, and I need to remove it. Would it be better to dehydrate it with heat before trying to dissolve it?

Homework Statement Some KCl is dissolved in water at 25°C, where it completely dissociates. The vapor pressure of pure water at 25°C is 28.3 mmHg. Estimate the mass in grams of KCl needed per liter of pure water to reduce the vapor pressure of water at 25°C by 5%. Homework EquationsThe Attempt...

I'm curious, in many flavors used in food (such as vanilla extract and other "natural flavors"), ethanol is used as a solvent to extract the flavors. Is this ethanol synthetic ethanol, or do companies normally get it from the wine/beer industries?

I know aqueous Ammonium Bicarbonate forms when NH4+ and HCO3- ions are present in water after they've dissolved from their gaseous states of NH3(g) and CO2(g). This occurs in the reaction: NH3(g) + H2O(l) + CO2(g) => (NH4)HCO3(aq) If Ammonia gas and CO2 are present above a polar organic...

Say for example you have take a sample of 500ml from a bulk saline solution (NaCl and H20). If you know that for every 100 grams of water there is 10 grams of NaCl, can you calculate the amount of NaCl in 500ml of the final mixture?

We are constructing a dip coater in our laboratory. But because of the disparity between the lowest and highest speed it was suggeted that maybe the initial dipping could be performed by keeping the sample ( ie substrate to be dipped) stationary and elevating the solution until the sample is...

Homework Statement Given for polystyrene K = 1.6x10^5 and a = 0.71 and for PVC K = 1.5x10^5 and a = 0.77 a universal calibration curve has been created from PS and the molar mass of PVC at a certain elution volume has been calculated. The part I'm not sure on is the question: Show which of...

Homework Statement http://i.minus.com/juL6gvGzvWdm.png Homework Equations Raoult's law: Pressure of solution = Mole fraction of solvent multiplied by vapor pressure of pure solvent. We're assuming non-volatile solutes. The Attempt at a Solution My solution...

Hi, I got a graphene dispersion on ebay but the graphene flakes cumulated at the bottom of the bottle. I'm trying to mix it and then solve in water using an ultrasonic cleaner but the flakes do not dissolve in water? How can I dissolve it so that I can obtain a large scale graphene by...

Water solvent is usually considered and essential basis for any Life in the Universe. Recently other solvents have been considered (eg Ammonia), but maybe we could come up with an idea of life that doesn't need solvent at all? As far as I understand solvent is need mainly as medium of...

So I have been asked to separate a polymer (polyurethane) into high molecular weight and low molecular weight components. I have access to Sephadex LH-20, a simple glass column, acetone (a List II chemical), ethyl acetate, and hexane. I may be able to get access to other solvents, as long as it...

How does polarity of the solvent affect the Rf value? I was going over a problem in my book that said that polarity would increase the Rf value of both the polar and nonpolar analyte due to increased solubility. This doesn't make sense to me because wouldn't the solubility of the nonpolar...

So, CO2 is said to be non polar because of its molecular geometry. However the carbon atom has two positive charges and the oxygens, one partial charge each. Therefore, why doesn't CO2 dissolve ionic molecules like NaCl? We've been taught that a polar molecule is one that can separate ionic...

I am looking for a solvent that can dissolve photo setting resin after it has been hardened. I think it is Diazo resin or something like it. Can anyone suggest something? Thanks!

how can I create a spheric glass ball or a closed cylinder containing a solvent as acetone or methanol? the ideal would be without air bubble inside and diameter in the range of 2-4 mm thanx max

Hello, I just want to make sure that my calculations are correct before doing an experiment. I need to dilute 250ml of 1.5M Cu(NO3)2 to 0.5M and distilled water is to be used as the solvent. So I'm not sure how much (volume) of distilled water need to be added. I used the equation C1xV1=C2xV2...

Hi, I'm a 1st-time poster in the chemistry forum. (Only did 1 year of chem at Uni.) I'm trying to understand the content of an organic paint-additive product "Penetrol". http://www.floodaustralia.net/products/paint_additives/penetrol.php The MSDS can be downloaded from this page...

Why is wine a solvent but sugar is not?

Why is alcohol better at dissolving compounds in herbs than water? Such as alkaloids and resins. Can someone explain how it actually does this?

Really I'm looking for a good carrying agent that will dissolve paraffin wax, but preferably that also evaporates quickly AND doesn't come with serious health concerns. Basically, I'm trying to make a rust inhibitor using paraffin...where it can be applied and then the solvent evaporates...

I know that the vapor pressure of a solvent would decrease with a changing concentration if there was an addition of a solute. However, would the vapor pressure change with a changing concentration of the pure solvent (no solute added)?

Hello, my name is Rudy and this is my first post. I am a gun owner and I am wondering about how to clean my rifle and all the accumulated residue derived from my military surplus ammunition which has Potassium Chloride in the Primers. After shooting the rifle, the Potassium Chloride gets into...

I am having trouble figuring out why this statement is true, especially the bolded sentence: "When the nucleophile and/or electrophile have a formal charge, SN2 reaction rate is fastest when the solvent is of modest polarity. When the nucelophile and electrophile are both neutral, SN2...

I am planning to use a gamma ray densitometer to measure the local concentration of slurry flow in a pipe loop. Since i am using an organic solvent(flammable) to make the slurry, i am worried that gamma ray passing through it will heat it up significantly and cause hazard. I would like to...

Hi chemistry friends, I'm currently working on a reaction to produce the following polymer: Cyclopentadiene functionalized polyketone. I start with polyketone as a reagent and I should end up with the reaction product together with the solvent (THF) and water with NaOH. My question...

Hi all! I am searching for solvent based liquid glue for adhering 2 transparent PET sheets together. I tried chloroform and dichloromethane, the PET sheets were adhered but resulting of opaque white fog on my transparent PET sheets. Could someone please advice me another nonbranded chemical...

Dear all, here's my first request for a little help (maybe also in finding the proper subforum...) I'm working as developer and scientific consultant in a lab for Nuclear Magnetic Resonance at high field (> 21 Tesla), and I have to create a suitable probe for checking the stability of a...

Hello! I was looking into haloalkane reactions and the factors which determine the proportion of nucleophilic substitution to elimination reactions. I read that ethanol is more conducive to elimination reactions than substitution reactions, it mentions it being less polar than water, which...

Hi I was just wondering why we use ice cold solvent when performing a filtration before vacuum filtration? What exactly does it do? Like ice cold alcohol? I know it allows filtration to be more efficient, but how exactly?

Homeopathic remedies "can be easily distinguished from the pure solvent"...