Questions tagged [experimental-chemistry]
This tag should be applied to questions relating to the theory, design, techniques or performance of chemical experiments. This includes but is not limited to theoretical structures, expected products, thermal calculations, and empirical analysis. Additional tags should be applied to narrow down the field of research.
1,655
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Stability of camphor
I was doing a lab experiment today in school and spilled a few drops of water into a ~.3 g camphor product. To remove the water in order to conduct a melting point test, my thought is to heat the ...
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What are the products of reaction when Zn(NO₃)₂·6H₂O and Fe(NO₃)₃(H₂O)₉ are dissolved in 2-methoxy ethanol i.e. C3H8O2 and reacted at 400°C
I prepared a thin film of ZnFe2O4 on ITO substrate by spin coating. For this I dissolved Zn(NO₃)₂·6H₂O and Fe(NO₃)₃(H₂O)₉ in (molar ratio 1:2) in 2 methoxy ethanol i.e.C3H8O2 and then spin coated ...
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What are the products of reaction when Nickel nitrate hexahydrate i.e. Ni(NO₃)₂6H₂O and 2-methoxy ethanol i.e. C3H8O2 are reacted at 400°C
I prepared a thin film of NiO on Quartz substrate by spin coating. For this I dissolved nickel(II) nitrate hexahydrate i.e. Ni(NO₃)₂6H₂O in 2 methoxy ethanol i.e. C3H8O2 and calcined (annealed or ...
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AlCl3 stuck to Pyrex
I made $\ce{AlCl3 . 6 H2O}$ the easy way, with $\ce{HCl}$ and foil. After filtering and reducing on the stove, I get a nice yellow crystal of contaminated $\ce{AlCl3 . 6 H2O}$. The yellow should be ...
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46
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Mislabelled figure in published paper? [closed]
Recently I discovered that an axis of one the figures from a paper that I published was mislabelled. Unfortunately, the figure also is the graphical abstract. However, the information in the text ...
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3
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0
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21
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Reaction of BTNA, DMSO, and phosphate?
I prepared a solution of n-benzoyl L-tyrosine p-nitroanilide (BTNA) in dimethyl sulfoxide for use in an enzymatic assay. However, mixing it with a solution of phosphate buffer produced a color change ...
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2
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Water Electrolysis Efficiency
During my water electrolysis with NaOH, I measured the voltage and current, and the volume of gases (hydrogen and oxygen) displaced at every 30-second interval. 10g NaOH in 2L water for 8 minutes.
...
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3
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0
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Why the change of the position of the salt bridge or metal piece leads to different voltage value?
I am doing an experiment where I use salt bridge to create galvanic cell. The goal of my experiment is to find if there is some correlation between the amount of solvent being used and the voltage ...
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1
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what is the meaning by 'species' of glycine? [closed]
The question ask for the species of the (i) glycine hydrochloride (ii) glycine titrated with NaOH. When they mentioned 'species', what did they mean by it?
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Functional group for glycine that had being titrated (i) HCl (ii)NaOH
i am kinda confused with this question. They asked for the functional group of (i) glycine hydrochloride (ii) glycine that titrated with NaOH. I did take a look many times especially for glycine ...
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2
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428
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Can ICE tables give two answers?
I was recently given the question:
The equilibrium constant, K, for the following reaction:
N₂(g) + O₂(g) ↔ 2NO(g)
is 4.00 x 10⁻² at a very high temperature. The reaction is at equilibrium at this ...
0
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0
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52
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What's the most efficient way to convert CaCO3 into Ca(OH)2?
I'm using the Calcium Looping process, where I have Calcium Hydroxide that converts into Calcium Carbonate. I'm trying to loop the Carbonate back to form Calcium Hydroxide.
So far, what I can find is ...
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1
answer
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synthetic procedure for 1,3,4 thiadiazole from acylhydrazide [closed]
I wanted to synthesize 1,3,4 thiadiazole-2- thiol substituted to benzoic acid the reaction has to happen in such a way that the "acid hydrazide" group of benzoic acid hydrazide has to ...
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battery using zinc, copper, and vinegar
I filed one side of a penny to reveal the zinc; then I bent the coin and dropped it into a cup of white vinegar. Shortly afterward, many tiny bubbles were forming on the zinc side. Later on, I noticed ...
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2
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Strange intermediate product when benzaldehyde undergoes Cannizzaro reaction
In the school laboratory, a friend tried the famous Cannizzaro reaction for benzaldehyde. Some $\ce{NaOH}$ was added to benzaldehyde, and the solution was stirred for 30 minutes. What came as a ...
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1
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Why does benzaldehyde turn yellow?
We used benzaldehyde for a demonstration of the Cannizzaro reaction in school, but the liquid we used appeared visibly yellow, as opposed to the colourless liquid described by Wikipedia.
A few reasons ...
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3
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1
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Are solid fuels with calorific values >= 10,000 kcal/kg (42 MJ/kg) physically possible?
I have seen laboratory documentation from a reputable lab in southeast Asia that a company has achieved a solid fuel product made from landfill material with a high heating calorific value ($CV$) of ...
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Why is Fe-P in NaOH part of Hieltjes & Lijklema (1980) P fractionation?
Background:
In order to separate the different phosphorus (P) species in lake or marine sediments, one can use sequential P fractionation method. Its main idea is to use extractants with weak or ...
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1
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Salt analysis (cation) [closed]
I'm reading about salt analysis and I've got some questions:
Image source: pdf
Why are some sulphides (group II) precipitated in presence of HCl while others (group IV) in presence of ammonia ...
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0
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How can the heat equation be used to model temperature vs time in a solubility experiment?
Background:
I am doing experiments trying to map the practical solubility of a certain chemical species called an "activator" solution. This solution is essentially a sequential mixture of ...
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1
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Chemistry behind adding methyl salicylate to iodine dissolved in petroleum jelly [closed]
We did a project at my school where we were asked to create a pain-relieving balm, inspired by Iodex. We first took 50gms of petroleum jelly and heated it in a water bath until it melted and became a ...
0
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1
answer
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How does Hess' Law work exactly? [closed]
So I am talking about complicated compounds and not simple reactions where you subtract heats of formation. I was trying to find the heat of reaction for an aryl substituted methyl aryl sulfide being ...
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Why do we cool the solution after melting it?
We conducted an experiment to analyze the molar mass of a solid by observing the freezing point depression it brought to cyclohexane. In short, the experiment procedure is as follows
the freezing ...
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0
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Why is it recommended to not store commercial sodium silicate solutions in direct sunlight, what are the effects of doing so and can it be modelled?
I regularly purchase aqueous sodium silicate solutions from commercial providers for my studies and note that a storage recommendation for all different grades (i.e. differing $\ce{SiO2 / Na2O}$ ...
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3
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314
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What is mAh/g Specific capacity?
In battery chemistry I've been reading about specific capacities of various electrochemical cells as $\pu{mAh/g}$. For example, in one article it says the specific capacity of the system is $\pu{75 ...
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82
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Notation for spectral density in experimental community
In an open quantum system setup where the system is coupled to infinite harmonic oscillators as bath (as in the Caldeira leggett model, for example), through the Hamiltonian,
$$H = \frac{\hat{p}^2}{2m}...
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What happens when iron(III) chloride is dissolved in ethanol?
I dissolved $\pu{25 mmol}$ $\ce{FeCl3*6H2O}$ in $\pu{25 ml}$ ethanol and got a clear ethanol solution of $\ce{FeCl3}$ 4 days ago. And I keep it in a drawer from light these four days.
However, when I ...
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3
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1
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173
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How to Choose the Appropriate Spindle and RPM in Rotary Viscometer for Viscosity Measurement of a Suspension Sample?
I am currently conducting a method validation for the analysis of a suspension. This would be the first time we will be conducting viscosity analysis via rotary viscometer and the below statements are ...
3
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1
answer
147
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How can combusted methane from landfill samples be quantified?
Background:
For my studies I'm wanting and attempting to make a landfill greenhouse gas emissions (GHG) model that predicts the amount of greenhouse gas equivalent emissions ($GHG_\mathrm{eq}$ [tonnes/...
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2
votes
1
answer
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How do different x-ray tube emission profiles (i.e copper vs cobalt sources) affect XRD samples containing iron (results included)?
Background:
I'm a student and have recently done some XRD on some iron ore mine tailings which came from an Australian mine tailings storage dam. The redness in colour and industry source led me to ...
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1
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204
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Calculating rate constant for reaction between ethyl acetate and sodium hydroxide
My research question is investigating how temperature affects the rate constant for the reaction between ethyl ethanoate (acetate) and sodium hydroxide. I understand that I must titrate sodium ...
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0
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Can dichloromethane be used as a replacement for chloroform in the MBAS assay?
I'm trying to perform an MBAS assay but my supervisor says we do not have chloroform available. I was wondering if dichloromethane would do the trick in its place i.e. filtering out any anionic ...
2
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1
answer
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Finding a Heterogeneous Catalyst for Hydrogen Peroxide
I'm designing an experiment to test the effect of surface area of a catalyst on the activation energy of hydrogen peroxide decomposition. However, I don't think I can use a powdered catalyst because ...
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1
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756
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Does germanium(IV) chloride have to be handled under inert atmosphere?
I am finding conflicting information on the proper handling of germanium(IV) chloride. Is the liquid air/moisture sensitive? Does $\ce{GeCl4}$ have to be handled in a glove box?
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1
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Are there any methods to dry a wet chemical sample within roughly half an hour?
I am planning an experiment for a school project. I have roughly 50 minutes (not including equipment preparations) to perform my experiment, which aims to experimentally verify how Ksp changes with ...
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0
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How to calculate composition of alcohol/water mixture to achieve given concentration of alcohol vapors in air for calibrating a DIY breathalyzer?
I made a breathalyzer using a MiCS-5524 gas sensor. I would like to calibrate it so it can be close to accurate. e2v technologies — MiCS Application Note 4, Using MiCS Sensors for Alcohol Detection (...
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3
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1
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Contaminants in Ion Exchange Chromatography significance?
I am a high school senior and decided to do a project on the essential amino acid composition of varying vegan protein mixtures. I have run into a problem concerning protein purification. One of the ...
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1
answer
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Is it possible for an appropriately vaporized crystal to have vapor properties in any way related to it's crystal? [closed]
Is it possible for an appropriately vaporized$^{1}$ crystal to have vapor properties in any way$^{2}$ related to it's crystal, or unique to the fact it was a crystal in it's previous phase?
The ...
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0
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Erythritol oxidation using acidified KMnO4
I have recently experimented with erythritol oxidation my primary aim was to make glyoxal. However regarding the nature and structure of erythritol several other side-products were also observed one ...
0
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1
answer
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Is there any calcium carbonate analogue drawing carbon from dry air?
Is there a nonliving (wood does not count) substance or process that accretes a solid material by withdrawing carbon from the air, in a manner analogous to calcium carbonate being accreted from ...
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Why is silver considered a "type 1" metal although it has multiple oxidation states? [closed]
I noticed that the metals I learned were "type 1" back in early chemistry class as they have one oxidation state including silver, aluminum, zinc, and cadmium. However, those metals weren't ...
0
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2
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384
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Reversible endothermic reaction
Is there an endothermic reaction that is reversible simple by adding heat? For instance, can I put chemicals in an enclosed tube that will react to release heat, then I can add heat and reverse the ...
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Can I use a mechanical pipette to transfer strong acid?
I am an undergraduate student majoring in physics. I am looking for the best method to accurately measure the volume of strong acids like hydrobromic $(w(\ce{HBr(aq)}) = 48\,\%)$ and hydroiodic $(w(\...
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2
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Looking For Resources on Separating Iron, Silicon Dioxide, and Sodium Chloride [closed]
I am working on an experiment and lab report for my high school chemistry course where I am given a vial with a mixture of Ferrum, silicon dioxide, and sodium chloride. I need to figure out how to ...
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0
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Why does Bachmann reaction differ in batch characteristics as opposed to flow characteristics
I have studied this reaction for over a year and it makes zero sense. When synthesizing HMX from Bachmann reaction, an important intermediate is DPT. DPT is formed by reaction of nitric and hexamine ...
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How does one achieve a non-stick layer over a copper plate?
We normally perform the process of coating of aluminum on BOPP under vacuum.
In this process, we use a copper material holder to electrically evaporate the aluminum. With this, the balance aluminum ...
2
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0
answers
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Are volatile impurities an issue for sublimation as a purification method?
Recrystallization depends on identical solute molecules colliding so that a crystal can grow. An impurity present in low concentration will generally remain in solution because kinetics will favor ...
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1
answer
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What are some good synthetic samples I can make myself to start getting better at Quantitative X-Ray Diffraction?
I'm a student wanting to become an expert in quantitative X-Ray Diffraction (QXRD) to determine the wt%s of both crystalline and amorphous phases in a solid specimen. At my university I have access to ...
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0
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What conclusions can I draw from this graph?
I've been doing an experiment where we would have copper chloride in an aqueous solution, and then mix aluminium foil in it which produces copper. We then modified that experiment to do the same thing,...
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3
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0
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Regioselectivity in oxo-Diels-Alder reaction
I have one doubt about the dimerization of methacryloyl chloride into the product 3:
The dimerized product was observerd around 10-15mol% in different commercial samples of methacryloyl chloride, as ...
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