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.
1,180
questions
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0answers
16 views
Why the mass of magnesium and acid increase after the reaction is done [on hold]
Help please
Why the mass of magnesium and acid increases after the reaction is done between the two?
0
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1answer
34 views
Is the rate of electrolysis the same throughout as long as voltage is same
In an electrolytic cell, where the electrolysis of dilute sulfuric acid is taking place, would the rate of electrolysis be constant always, even at the beginning?
By rate of electrolysis, I mean the ...
2
votes
2answers
58 views
Will mixing hydrogen and oxygen without a spark result in combustion?
I plan to do the electrolysis of dilute sulphuric acid. This will produce hydrogen gas and oxygen gas at the anodes. I do not plan to collect these gases, but to simply let it form and release into ...
3
votes
1answer
56 views
Producing soap from sodium carbonate and oil
Can we get soap by mixing $\ce{Na2CO3}$ from seaweeds with oil? I am not good at chemistry and saw this in an anime Dr. Stone, so I just wanted to know if it is true or not.
-1
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0answers
13 views
Calculating Percent Yield [closed]
Aluminum oxide is produced in a single replacement reaction between aluminum and chromium (II) oxide. Calculate the percent yield if 603.0g of chromium(II) oxide were used with 422.5g of aluminum and ...
-1
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0answers
57 views
NH4NO3 + NaOH What is this weird floating precipitate?
In a reaction $\pu{110\\g}$ of $\ce{NaOH}$ and $\pu{90\\g}$ of $\ce{NH4NO3}$ are combined in approximately $\pu{500\\mL}$ of water. An unknown foam appeared. This foam however acts more like a ...
17
votes
5answers
3k views
Why isn't pressure filtration popular compared to vacuum filtration?
I want to build a DIY vacuum filtration apparatus with a bike pump but it's very difficult to find one the could be easily converted into a vacuum pump. This prompted an idea to simply build a reverse ...
2
votes
1answer
41 views
Sodium metal burning off when conducting electrolysis and I don't know why
I melted down some table salt and used high voltage welder power source to try and separate the sodium and chlorine it was partially successful because I could smell and see chlorine gas but during ...
1
vote
1answer
29 views
How hot will a carbon electrode get in an electrolysis setup?
For the electrolysis of sulfuric acid, I plan to use carbon graphite electrodes at voltages up to 6 V. I would like to know if my carbon electrodes would get considerably hot or warm (45 °C or higher)....
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1answer
37 views
Would this experiment be electrolysis experiment be viable?
I plan to do a 'research project' or an experiment involving the electrolysis of dilute sulfuric acid.
The idea or 'question' is this:
Would there be a variation in the $\mathrm{pH}$ of the ...
1
vote
0answers
35 views
Are portable pen pH-meters accurate?
Are pen $\mathrm{pH}$-meters accurate? I know there are large table-top $\mathrm{pH}$-meters, but I keep seeing these small $\mathrm{pH}$-meters online that can read up to 0.1 units. My question is if ...
4
votes
1answer
46 views
What chemical could dissolve low-density polyethylene?
What chemical could dissolve plastic aside from acetone? Preferably, low-cost and environmentally friendly. Any suggestions would be helpful.
I'm targeting for thin plastic (low-density polyethylene)....
1
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0answers
20 views
How do you purify phosphoric acid from cheap commercial (hardware-store) products?
I am looking for idea's on how to purify phosphoric acid for lab use, as the the price for reagent grade V's home-use ended with me buying a product designed as a rust-killer for steel... The ...
-2
votes
1answer
27 views
Occurence of double displacement reaction [duplicate]
$\ce{AgNO3 + NaCl}$ gives $\ce{NaNO3 + AgCl}$ but why it's vice versa is not possible. My question is how to predict if a double displacement reaction will occur naturally or not.
19
votes
2answers
2k views
Does ultrasonic bath cleaning damage laboratory volumetric glassware calibration?
As an analytical chemist, I'm always ensuring my glassware is thoroughly clean before I start an analysis. However, my supervisor always states that using ultrasonic bath to clean volumetric glassware ...
1
vote
1answer
63 views
Can antimony pentafluoride be made by adding hydrogen fluoride to antimony trifluoride?
I was looking at how the strongest acid was made and I found something I did not understand. On the Wikipedia page for antimony trifluoride it shows the production of $\ce{SbF3}$ using $\ce{HF}$:
$$\...
1
vote
1answer
42 views
Temperature and pressure for three phase equilibrium of aqueous sodium chloride solutions
I am currently investigating the effect of adding Salt(NaCl) to water on its triple point. Let us assume the mass ratio of water to NaCl is $1:1$. I asked a similar question previously. But, I still ...
2
votes
1answer
37 views
Iron(III) nitrate and hydrogen peroxide reaction
When iron(III) nitrate is added to hydrogen peroxide as a catalyst, the temperature initially decreases and begins to increase after 30 seconds. Why is this the case? (is there any intermediate ...
-3
votes
1answer
77 views
Burning magnesium ribbon [closed]
I know that this might sound wrong but, in the reaction
$$\ce{2 Mg(s) + O2(g) → 2 MgO(s) + energy}$$
isn't oxygen supposed to be oxidised as it has excess electrons $(\ce{O^2-})$ and can donate a ...
-1
votes
0answers
20 views
How to determine which liquid has higher antioxidant content?
If I have two solutions with me and I want to find out which one has a greater antioxidant content then how can I experimentally find that out in a laboratory? What are the chemical reactions? The two ...
5
votes
1answer
48 views
How can I figure out if my store bought chlorine is the percentage it says it is?
Chlorine is an important part of maintaining any pool. I've read horror stories of people buying chlorine from pool stores or big box stores and the chlorine being ineffective.
If stored long enough ...
0
votes
1answer
48 views
How can I neutralise H2 gas without burning it? [closed]
I was thinking of maybe making it bubble into a solution containing something that would react with H2 yielding either a dissolved substance or a precipitate from the reaction.
Maybe a solution with ...
1
vote
1answer
31 views
Can I safely use a separatory funnel to extract the precipitate from a solution?
Can a separatory funnel be used to collect a precipitate, or would that risk clogging the stopcock on it?
I'd like to recoup the precipitate for filtering without passing the entire solution through ...
2
votes
0answers
50 views
How does a pH glass electrode work?
Every source I read mentions the potential difference building up at the glass membrane (according to the Nernst equation). But how is this difference actually measured? Sticking an electrode into a ...
8
votes
1answer
1k views
What does “lit.” mean in boiling point or melting point specification?
For example, this Xanthene 99% specification from Sigma Aldrich states:
\begin{array} \\\hline
\text{bp} & 310-312 ~^\circ\mathrm{C~ (lit.)} \\\hline
\text{mp} & 101-102 ~^\circ\mathrm{C~ (...
0
votes
1answer
37 views
Why does steam distillation work?
I'm aware that there is a similar question here but it didn't really answer my specific questions.
I understand that steam distillation is used to separate an insoluble liquid from an aqueous solution,...
0
votes
1answer
43 views
What should be the molarity of HCl and H2SO4 acid so that they can be considered safe to touch? [closed]
I know $\ce{HCl}$ and $\ce{H2SO4}$ acid of concentration 17 M is dangerous and corrosive, but I wonder can we dilute these acids to the extent that they become safe to touch?
If yes, then what should ...
2
votes
1answer
49 views
Can I use litmus paper to test unknown liquid that contains a concentrated strong acid?
Can I use litmus paper to test unknown liquid that contains a concentrated strong acid (example $\ce{H2SO4}$)? Can concentrated strong acid destroy litmus paper?
3
votes
1answer
52 views
How do I remove tetrabutylammonium perchlorate from an organic synthesis?
I am trying to remove tetrabutylammonium perchlorate (TBAP) from an organic synthesis where TBAP was used as an electrolyte. I am working with compounds containing the amide group. I have used flash ...
1
vote
1answer
41 views
Will strong concentrated acid destroy litmus paper and pH paper if they are dipped in acid?
I am curious to know what will happen if I have litmus paper and pH paper, and I dip them into strong concentrated acid like conc. $\ce{H2SO4}$ to test its acidity or basicity. Will acid destroy ...
-1
votes
1answer
61 views
Method for removing CuO in an inert environment
Common oxides (i.e., CuO or Al2O3) are capable of removal via NaOH solution. However, I am interested in removing a copper oxide layer inside an inert (Ar glovebox) environment. Thus, the traditional ...
1
vote
0answers
33 views
Does boric acid catalyze esterifications with isopropanol?
I am going to synthetise isopropyl salicylate. From what I have read on phillysim.org (pdf) the formation of ethyl salicylate can be catalyzed by boric acid. I could use sulfuric acid but it would be ...
6
votes
3answers
2k views
How much salt (or any other substance one can find in a kitchen) do I need to add to make water boil at 104 °C? [closed]
I've seen some formulas around in other questions and Google searches, but my chemistry is pretty much dead so I have no clue where to find the relevant values to calculate it myself. I just need to ...
1
vote
0answers
18 views
Difference between acetocarmine and feulgen stain [closed]
We did an experiment on observing mitosis in onion root tip cells, and I have observed that there are two ways of staining it, using acetocarmine and feulgen stain. What are the advantages of using ...
8
votes
0answers
46 views
Quantitative Transfer of Volatile Standards
(Edited w/ updates) Okay, long story short I work in a lab which has been working on cannabinoid analysis (in the licensed Canadian market) and have had a lot of issues surrounding the standards/...
4
votes
1answer
45 views
Identifying an extra NMR peak in silyl protection reaction
I protected a phenol with the TIPSCl/triethylamine procedure. The product was isolated by column (hexanes/EtOAc) and shows an extra singlet at 1.05 ppm in $\ce{CDCl3}$, integrating to ~10 H. Whatever ...
2
votes
1answer
92 views
Synthesis of Aspirin, made unknown fluid
When I tried synthesising aspirin, after quenching and cooling it I noticed a translucent, milky, white fluid floating in the solution.
The method used was:
Salicylic acid (2 ml) was added to ...
1
vote
0answers
40 views
What could be causing my cyclic voltammograms to have a sloped scan?
I am running a CV (cyclic voltammogram) in a two compartment bulk electrolysis cell with pH 7 phosphate buffer (0.5 ion concentration) and a napheon membrane separating the two compartments. I'm using ...
-1
votes
1answer
23 views
Prolonging the exothermic reaction between calcium oxide and water
Is it possible to generate 10-minutes of heat using very small amounts of CaO and water? This is an exothermic reaction.
I've done this experiment at home, but it is very short-lived. I'm trying to ...
3
votes
1answer
41 views
How to capture the gas produced by combusting alcohols
I am burning various alcohols and am attempting to capture the carbon dioxide produced. I could burn the alcohols in a conical flask with a cork on the top, with a tube directing the gas into a gas ...
0
votes
0answers
39 views
Why does the following “Battery” experiment work?
I did the following experiment:
Experimental setup:
Two electrodes (one made out of Iron,the other made out of Copper)
are put into a (bluish) Copper(ii) sulfate lotion.
Then, one connect a ...
0
votes
0answers
49 views
How to effectively get rid of 2-propanol acetate vapors and smell
I need to get rid of 2-propanol acetate vapors and its smell and need some chemistry help.
Some possibilities I came up with:
soap and water to rinse surfaces because soap might help increase its ...
4
votes
0answers
58 views
An unknown glassware piece from our cupboard
We have multiple of these. It is a small glass funnel with splits into 3 spouts from it. Now, we are thinking it might be similar to a cow receiver, however, I have never seen one this small or ...
4
votes
0answers
30 views
Unknown possibly handmade glassware- description in information below
Okay, Another random item from the cupboard (unknown users or discipline of life sciences unknown) could be anything up to 40 years old....
This appears to be a 2 neck quickfit adapter (B19 and B14) ...
0
votes
0answers
50 views
Unknown glassware please help, vshaped with a small bulb on one side, hollow but narrow to both sides!
Looking to try an identify some glassware we have found in a cupboard. This is just the start of it...
1 item here, v-shaped, small bulb but hollow, narrow entrance and exit...
1
vote
1answer
53 views
How can I check the sodium content of food?
What is an easy (i.e., home project) way to measure sodium in food?
For example, the nutritional label of a tahini brand that I often consume shows very little sodium (around 10mg/100g). I suspect ...
0
votes
1answer
49 views
Uncertainties Calculation
Recently I did an experiment on isolating casein and now that I am processing the results, I feel my method of uncertainty calculation is not feasible. The casein was isolated 3 times and the results ...
14
votes
1answer
1k views
Using a gas stove instead of Bunsen burner for a flame test?
In all chemistry labs we use the Bunsen burner. What's the difference between it and a good old gas stove used in home? Can the stove also be used to get positive flame tests for some cations (like $\...
2
votes
1answer
83 views
Why doesn't N2O give a positive brown ring test?
A common nitrate test, known as the brown ring test can be
performed by adding iron(II) sulfate to a solution of a nitrate, then
slowly adding concentrated sulfuric acid such that the acid forms a
...
0
votes
1answer
50 views
Can I determine purity of isopropanol with a hydrometer?
Assuming I start with a known 99.8% purity of isopropanol, after recovery with a distillation apparatus, could I use a hydrometer to test for water content? If so, is there a special one I should use?
