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.

Filter by
Sorted by
Tagged with
0
votes
2answers
46 views

Can you heat something at alcohol bath?

I have a mixture of $\ce{Et2O},$ $\ce{EtOH}$ and water, and I want to distill off the ether. I am using a water bath so not much water is distilled over, as the boiling water is 100 °C, and the ...
0
votes
0answers
12 views

Removing potash from water using poly-aluminum chloride

I have been conducting an experiment for a school project, (removing metals from water)I added 50 grams of sulphate of potash to 2 litres of water, then allowed it to dissolve for a 24hrs. On two ...
2
votes
2answers
621 views

Removing aluminum oxide from impure silica

We have an assay for a mine. Our goal is to have only silica. Is there a cost effective way to extract the contaminants? The product is a fine powder called diatomaceous earth, or fossil shell flour. ...
3
votes
1answer
63 views

Is it more precise to measure a substance as a solid or as a liquid?

If I have a substance and want to obtain an exact quantity of it, is it better to measure it as a solid or as a liquid? In other words, if I have, for example, NaCl crystals I can weigh the crystals ...
-1
votes
1answer
35 views

Is it possible to predict release of acid fumes in certain acid reactions? [on hold]

Upon mixing both acids, the reaction between Formic Acid and Sulfuric Acid, besides producing Carbon Monoxide and Water, releases a certain amount of acid fumes. Does anyone know if the fumes, in ...
0
votes
0answers
14 views

PV Cell materials for efficiency

I was watching a show on PV cells and said they can only get to 40% efficiency because of the materials that they are using. I was wondering if you can dope a different semiconductor substance like ...
8
votes
1answer
2k views

Role of methanol in NaBH4 reduction

In reduction of carbonyls (aldehyde and ketones) to alcohols using NaBH4/Methanol, alkoxides are formed with the Boron which usually gets protonated on addition of water/acid. My question is what is ...
2
votes
1answer
2k views

Will adding apple cider vinegar to freshly pressed fruit juice preserve it

Would adding apple cider vinegar to freshly cold pressed fruit juice be able to preserve the fruit juice and extend its shelf life? Would the juice change into vinegar with time?
1
vote
0answers
23 views

Measuring change in concentration of hydrogen peroxide

I am conducting an experiment to find the rate constant of the decomposition of hydrogen peroxide, $\ce{H2O2}.$ For this, I was planning on using the integrated rate law: $$\ln(\text{final ...
3
votes
1answer
29 views

What are the equations giving the molar flow of different molecules linked by a reaction?

Let consider a steady state CSTR in which occurs the following reaction: $$\ce{aA + bB \leftrightarrow cC}$$ Notations: $F_i$ is the molar flow of $i$, $r$ is the rate of reaction, $V$ is the ...
0
votes
1answer
40 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 ...
1
vote
1answer
91 views

Extrapolating from a calorimetry lab to find a new delta T with different volumes and grams of substance

So, we just finished an AP chem lab where the question was basically: Given the results of the lab were that $\pu{5 grams}$ of $\ce{CaCl2}$ and $\pu{45ml}$ of water produced a $\pu{13.33 ^\circ C}$...
-1
votes
2answers
32 views

Why does a NOx container get cold when NOx is released? and What is the relationship of the vapor pressure curve with the liquid-vapor dome?

The temperature at which $\ce{NO_x}$ is in equilibrium with its liquid and vapor phase at 1 atm is about –84 °C. Does that mean $\ce{NO_x}$ exists as a liquid at that temperature? What about it's ...
2
votes
0answers
20 views

How to remove the foggy discoloration in polycarbonate tubes caused by acetone?

Unknowing that the tubes used in the centrifuge are made of polycarbonate, I cleaned them with acetone. Following, a white smoky discolouration appeared and the tubes turned opaque. Is there any way ...
3
votes
4answers
126 views

Heisenberg's uncertainity principle(HUC)

I know the mathematical form of HUC and its statement i.e.It is impossible to determine simultaneously. , the exact position and momentum of an electron. i don't know why this ...
7
votes
1answer
113 views

Grignard reaction on electron-poor benzyl bromides

I am trying to prepare a Grignard reagent from 4-nitrobenzyl bromide but the reaction just doesn't work. My conditions are: 10 mL of THF (anhydrous); 7.04 mmol of 4-nitrobenzyl bromide; 7.04 mmol of ...
1
vote
2answers
44 views

Synthesis of potassium trioxalatocobaltate(III) trihydrate

I've synthesized the compound potassium trioxalatocobaltate(III) trihydrate and for it I have two reaction equations. One of them is: $$\ce{CoCO3 + 3K2C2O4.2H2O -> K2[Co(C2O4)3] + 2CO2}$$ and the ...
-1
votes
0answers
28 views

Formylation of an Indole [on hold]

What methods are available for the C-3 formylation of 2-phenylindole?
0
votes
1answer
160 views

How do I make a 0.5 M citrate buffer at pH 4.5?

I need to make a citrate-sodium citrate buffer at 0.5 M concentration and pH 4.5. I calculated the molarities of the citrate and disodium citrate based on the Henderson Hasselbalch equation, using a p�...
11
votes
1answer
820 views

What exactly is the Horwitz equation?

During a laboratory exercise in a course on analytical chemistry, we were asked to calculate the $z$-score. $$z=\frac{X_{\text{lab}}-X_{\text{cons}}}{S_{\text{target}}}$$ where $X_{\text{...
0
votes
0answers
26 views

Plaster of Paris

One of my Chemistry professors said that the hard mass formed after adding water to Plaster of Paris, cannot be converted back into Plaster of Paris. However, he said that the original Gypsum can be ...
-1
votes
1answer
2k views

Single Point vs. 5 Point Calibration in HPLC

Single-Point calibrations aren't that useful for quantitative analysis and there is more room for error in result readings as compared to a 5-Point calibration. Is this why a 5-Point calibration is ...
0
votes
0answers
24 views

error in making a series of standards out of a stock solution

I want to make a series of standards to make a calibration curve. The analyte is a volatile substance so I'll have to use some glass "containers" with a membrane lit so I don't lose too much of the ...
1
vote
1answer
6k views

finding cation of unknown salt in solution from precipitate

I should probably add that I was originally given an unknown solid mixture of 2 salts. I separated the insoluble salt out by centrifuging and then decanting. I found that the insoluble salt is $\ce{...
3
votes
1answer
125 views

Is there a known relation between the diffusion of a molecule and the diffusion of the reactants?

I have a plasma consisting of elements A and B (which have a similar mass). These elements can react to form molecules AB. $$ \ce{A + B -> AB} $$ Now if my plasma or gas is expanding based on ...
0
votes
1answer
27 views

Does aminosugars give positive response in alkaloid tests?

Does aminosugars give positive response to test for alkaloids such as tests with Dragendorff's reagent, mayer's reagent, Hager's reagent, Wagner's reagent etc?
3
votes
1answer
3k views

Best way to dissolve/emulsify beeswax and carnauba wax in water-based solution

What I can use to dissolve beeswax and carnauba wax and keep it in an aqueous solution? I do not want to use ethanol or acetone as they are too harsh. I am adding about $\pu{5\%}$ wax to a $\pu{16oz}$...
0
votes
0answers
11 views

In which order should you prepare a microemulsion?

So I have isoooctane (oil phase) ,CTAB (surfactant) ,1-butanol (cosurfactant) , and an aqueous solution of metal nitrates as the water phase. In which order should i add these components? Or any ...
0
votes
0answers
40 views

How much ethylacetate is produced?

1 mol of acetic acid and 1 mol of ethanol was mixed to react at a constant pressure to reach the equilibrium, and 0.75 mol of water was found in the product. A. Calculate the equilibrium ...
14
votes
5answers
8k views

Does increasing concentration of copper sulfate decrease or increase its conductivity?

I am a high school student and for my chemistry lab, I did an electrolyis experiment on how the changing concentration of electrolyte (copper sulfate) will change the rate at which the copper is ...
1
vote
1answer
44 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 ...
10
votes
3answers
2k views

Is argon preferred over nitrogen for maintaining an inert atmosphere?

I recently started a project in a new lab-group over Summer that does medicinal chemistry. Unlike in the undergraduate labs, they use argon instead of nitrogen for their inert atmosphere work. When I ...
0
votes
3answers
86 views

How Can I Induce Corrosion Electrochemically?

I'm very interested in measuring corrosion in metal alloys, particularly in salt solutions. I understand metals corrode over time, however, I was wondering if it's possible to electrochemically "speed ...
2
votes
2answers
66 views

Will mixing hydrogen and oxygen without a spark result in combustion? [duplicate]

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
62 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.
0
votes
2answers
78 views

How to evacuate a glass vessel containing powders?

I would like to evacuate a vessel (a glass round-bottomed flask) and which contains a few grams of platinum. However, I am worried about the platinum powder being sucked up by the vacuum. A few ...
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 ...
6
votes
2answers
6k views

Why is a volumetric flask shaped the way it is?

A volumetric flask does not look like an Erlenmeyer flask, but has more of a pear shape. Is it just to distinguish more easily between them while they are on the shelf?
1
vote
0answers
34 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 ...
2
votes
1answer
44 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 ...
2
votes
1answer
463 views

Distilling small volume

I have 50 ml of a compound I would like to purify. Since the impurities presents have close boiling points (b.p.), I have to use fractional distillation. Am I going to lose significant quantity of my ...
1
vote
1answer
31 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)....
1
vote
0answers
38 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 ...
-1
votes
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 ...
4
votes
1answer
52 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
vote
2answers
2k views

How to obtain calcium carbonate?

I read calcium carbonate is the main component of seashells and other animals' shells (such as snails), and also limestone. How can I prepare pure $\ce{CaCO_3}$? Could someone describe the process ...
2
votes
2answers
8k views

Mixing hydrochloric acid and sulphuric acid, both concentrated

In the chemistry lab, I stupidly decided to mix hydrochloric acid and sulphuric acid, both concentrated, in a random ratio, which was about $\pu{50 ml}$. When I poured them in one test tube, the ...
1
vote
1answer
88 views

Query in Chemical Kinetics

I have been recently studying chemical kinetics. I've understood what the rate law and the rate constant mean, and also that, kinetics depends completely on experimental observations, due to which we ...
1
vote
0answers
22 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 ...