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.
1,250
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5 views
Chlorine effect of carrageenan gel structure
I have a experiment with carrageenan and the result was there were a precipitation in the buttome when I used water with high chlorine but the gel is formed but it take a very long time to set. I just ...
2
votes
1answer
55 views
What reaction could rubidium undergo in a vacuumed chamber with Macor ceramic and glass?
In the center of the chamber on the photo below you can see the hexagonally-shaped Macor glass-ceramic consisting of
Silicon dioxide $\ce{SiO2}~46\%$
Magnesium dioxide $\ce{MgO}~17\%$
Aluminum ...
-1
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0answers
13 views
how does temperature affect the reaction rate of zinc and hydrochloric acid [closed]
how does temperature affect the speed of the reaction rate between zinc and hydrochloric acid? For example, does it even react when it's in cold temperatures or does it react slowly? Does the reaction ...
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0answers
14 views
To what extent do factors affecting rate of a reaction affect? [closed]
I am a high school student and planning to write an assessment on the subject of factors affection rate of a reaction. I would like to search for how much a factor affects. Is this a good subject and ...
3
votes
1answer
35 views
Calculating the total uncertainty of the final product
I have performed a large number of calculations in order to determine the ethanol content of wine. These included titrations using burettes, mass measurements using analytical balances, and others. I ...
-1
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1answer
53 views
Does Na⁺ and Cl⁻ recombine when water is boiled off from salt water? [closed]
When salt dissolves in water, $\ce{Na+}$ and $\ce{Cl-}$ ions are left floating around. When salt water is boiled, you are left with a white/powdery residue. Is this $\ce{NaCl}$ or is it a mixture of $\...
0
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0answers
11 views
Best desiccant for preserving large quantities of cotton
Without proper warehouse, freshly gathered cotton is piled in open air area spreading miles each way. It is covered by tarp during the rainy weather. What is a cheap/feasible method to keep it dry so ...
-1
votes
1answer
27 views
Copper wire smoking underwater [closed]
I am doing an electrolysis experiment with two copper wires inside of test tubes that are both submerged underwater, with 20 V per wire. Test tube A is creating oxygen gas at a high rate, but test ...
1
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0answers
12 views
Starch Amylase Experiment using Iodine
The starch and iodide test is to detect amylose, a polysaccharide. We add an iodide solution to a sample and observe a color change with the starch; it turns dark blue. I am doing a bio/chem ...
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0answers
20 views
Why ice crystals form at a very low temperature? [closed]
I don't know why ice crystals form at a very low temperature.
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0answers
23 views
lead nitrate in brown colour? [closed]
i have done a qualitative analysis lab this week and i had wierd thing i couldnt find an explenation to.
after mixing lead nitrate solution with sodium hydroxide a white fluffy residue appeard, when ...
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0answers
22 views
Reaction of hot sodium bicarbonate solution on aluminium foil
I was really curious about finding out how sodium bicarbonate reacts with aluminium metal. For this, I prepared a sodium bicarbonate solution and added a piece of aluminium foil to it. I scraped the ...
0
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1answer
34 views
what wavelength should I use to measure the transmittance of iodine colouring? [closed]
I am doing an experiment on how pH buffers may affect amylase's break down of starch into glucose in a starch solution. I am using iodine reagent to identify how much starch is left after amylase is ...
1
vote
0answers
31 views
How to clean pocket pH meter before storage?
Hello.
I read about different methods how to clean this specific(attached photo)pocket pH meter before storage and i can't figure out what is the right way.
One method says to stir the pH meter(...
0
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0answers
38 views
Why Does Adding Catalyst Slow Down My Reaction?
I currently did a lab where I was meant to identify factors that increase the rate of the reaction. I reacted Glucose with Potassium Permanganate and used Sulfuric Acid as a catalyst. But in my ...
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0answers
17 views
Salt recovery from brine solution
I have a solution of brine (NaCL) which after passing in to multiple effect evaporator its become saturated and some crystalline. We pass that solution in the centrifuge to recover salt but the ML ( ...
0
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1answer
29 views
What is the use of both mol and mass representing the same thing i.e. amount of something? [closed]
A mol is a unit but also has a magnitude. How can a unit have a magnitude? And if mole is used to measure an amount of substance than what does mass measure?
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1answer
26 views
Can there be a compound which stops the pesticide from entering into the fruit or vegetable? [closed]
Can there be a compound which stops the pesticide from entering into the fruit or vegetable? For example, a solution which is sprayed before pesticides and somehow blocks pesticides from entering into ...
10
votes
1answer
2k views
What is the scientific term to describe the operation of a bong?
What is the scientific term for the separation of dust particles from air by suction through a specialized flask in a way similar to the operation of a bong?
The thing that led me to this was a ...
1
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0answers
23 views
How to convert pepsin into powder form?
I have pepsin powder which is now hydrated due to humidity. I want to convert it back to the powder form. How to do it?
I don't have access to a freeze-dryer .
I prefer any cheap procedure other than ...
3
votes
2answers
62 views
Giving too much energy to an exothermic reaction [closed]
What will happen in an exothermic reaction if more than required energy is given? I mean, will it produce even more energy which will be highly dangerous or nothing will happen according to Le ...
1
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0answers
33 views
How to handle CO2 being evolved during vacuum distillation?
Setup: vacuum aspirator pump, distillation apparatus with stirring (instead of a bubbler). Partial vacuum around 5" Hg.
What would you suggest to hold the vacuum set-point?
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1answer
72 views
Do secondary alcohols react faster than primary alcohols or is it the other around? [closed]
My questions is that do secondary alcohols react faster than primary alcohols or is it the other around? This for the oxidation of the alcohol to a ketone or an aldehyde.
This reaction is with KMnO4 ...
1
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1answer
34 views
Methylammonium lead(II) iodide perovskites in bulk form
I am trying to obtain $\ce{(MA)PbI3}$ as a bulk powder using lead(II) iodide and methylammonium iodide as precursors.
I have not yet tried simply mixing the two in methanol/ethanol and removing the ...
1
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1answer
270 views
Reaction with tin(IV) iodide and hydrogen peroxide [closed]
Today I reacted tin(IV) iodide $\ce{SnI4}$ (dissolved in water) with hydrogen peroxide. This produced a yellow/brown colour (I'm guessing due to formation of $\ce{I2}?).$
I then added some petroleum ...
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0answers
21 views
Is the graph that is attached (a form of the arrhenius equation) only used when the temperature is varied? [closed]
determine the approximate value of Ea with its appropriate units.
In my lab course, I am doing an experiment on the rate of reaction, but all three of my trials were using the same temperature. That ...
1
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1answer
51 views
Acid-base titration: Unknown base in burette or flask?
While finding the concentration of $\ce{NaOH}$ via titration with $\pu{0.05M}$ Oxalic acid solution (in our lab) we put NaOH in the burette whereas added phenolphthalein to oxalic acid in titration ...
2
votes
1answer
57 views
Why do bubbles form when a reactive metal is placed in a less reactive metal's salt solution?
What is the gas that if formed when a reactive metal is placed in a salt solution of a less reactive metal? Theoretically, it should just be a simple displacement.
I know that this question has been ...
1
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0answers
38 views
Explanation for the reaction of gold and iodine(iii) solution
The Experiment
A few days ago I saw a video of dissolving gold in the condition of $\ce{ICl3/HCl(aq)}$. In the video, $\ce{ICl3(s)}$ is added to a test tube, followed by adding conc. hydrochloric acid....
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votes
1answer
40 views
Can you achieve plasma charge? [closed]
This question might be too common, but I'm very curious to understand and find out if this is possible.
We see a lot of sci-fi movies and TV series where they have plasma guns, in reality is this ...
3
votes
0answers
35 views
What gas would be suited best to form a density gradient in a long tube? [closed]
I want to set up an aero-optics experiment using a sealed ~5 m length of pipe with a gas inside. The gas must form a density gradient, and must be transparent enough to view a target at the other end ...
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0answers
31 views
Calibration curves and dilution factors
I am currently taking a course where we are exploring nitrate concentrations in water samples. We are using a UV-Vis Spectrophotometer and have created a calibration curve in the first part of the ...
-4
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1answer
40 views
Aluminum Oxide + Epsom salt ⮕ aluminum sulphate + Magnesium oxide [closed]
I was wondering that if you wrapped some Epsom salt in aluminum foil and set it on fire would you get aluminum sulphate and magnesium oxide, I couldn't find anything about this on the internet
2
votes
0answers
57 views
How to counter crust formation when crystallizing NaCl on the liquid-air interface?
Saturated sodium chloride solutions are evaporated at elevated temperature. The aim of evaporation is to produce hollow pyramid salt crystals. Temperatures used range from 65°C to 85°C. With 80°C ...
-1
votes
1answer
152 views
Titration/ Separating Soluble Salts/ NaHSO4
When performing titration between NaOH and H2SO4, both Na2SO4 and NaHSO4 are formed (both are soluble in water), is there any method to obtain crystals of NaHSO4? (Maybe by separating two soluble ...
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0answers
40 views
Electric fields in a galvanic cell
I have read hat there is two types of electric fields exist in galvanic cell.I understand E because of charges accumulated on electrodes but what about other E -field? What does cause this field and ...
0
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0answers
39 views
Balanced equation for Schweizer's reagent production?
In Thompson's Illustrated Guide to Home Chemistry Experiments the chemical formula for Schweizer's reagent is represented as $\ce{[Cu(NH3)4](OH)2}$ (although Wikipedia represents it as $\ce{[Cu(NH3)4(...
-4
votes
1answer
83 views
ml/min to mol/min [closed]
After completing a continuous distillation experiment, i am trying to convert my feed flow which i set to 30 ml/min and into mol/min to determine a mass balance equation.
If i use the equation below ...
3
votes
0answers
34 views
Molar ratios not leading to complete reaction in Schweizer's reagent production
In my home lab, I've reacted $\ce{Cu(OH)2}$ with aqueous ammonia to produce Schweizer's reagent. However, I'm surprised by the amount of ammonia required to react with this amount of $\ce{Cu(OH)2}$. ...
1
vote
1answer
61 views
Coffee Degassing
I roast coffee, and currently package it in plastic bags with one way 'degassing' valves.
As soon as coffee is roasted, it starts giving off $\ce{CO2},$ a process which continues for days, and ...
6
votes
2answers
87 views
How to weight picric acid?
Picric acid is stored under a layer of water to prevent an explosion.
What is the right way to measure the amount of picric acid that taken out? It is wet and containing water.
1
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1answer
222 views
Making aspirin without acetic anhydride
I want to make aspirin. Normal method is to react salicylic acid with acetic anhydride, but it is extremely hard to find acetic anhydride. How may I synthesize aspirin with acetic acid and salicylic ...
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0answers
37 views
Iodine Clock Reaction with Iodine Tincture and Tap Water
After unsuccessfully doing an iodine clock reaction at my school and being unable to collect any useful data, my teacher decided not to give me any more lab time. This lead me to have to find an ...
6
votes
1answer
133 views
Why does thallium hydroxide increase the yield of product in a Suzuki reaction?
I came across a research paper by Uenishi et al. [1] where relative rates of $\ce{KOH}$ and $\ce{TlOH}$ in Suzuki coupling reactions are compared.
Thallium hydroxide increased the yield of products, ...
0
votes
1answer
42 views
Separation of Methanol-water in a plate distillation column
I conducted an experiment to separate methanol and water. I am trying to determine the mole fraction of the distillate collected but having a little trouble with the calculation.
So i had a flow rate ...
0
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1answer
61 views
Is it possible to make micelles to pick up Microplastics from water?
I'd like to know if I could get micelles to pick up microplastics in water. I read that microplastics are sometimes charged, so can we make the lyophobic end to pick up microplastics, so that they can ...
-1
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1answer
44 views
32 Degree Thermochomic dye [closed]
I am doing a school project which involves color changing based off of temperature, and I need a thermochromic dye that changes color at 32 degrees Fahrenheit. Does anyone know where I could find some ...
0
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0answers
20 views
Fat polymerization vs hydrolysis and temperature change
I have an experiment on fats that I have to do in a few hours and I am very lost between fat/oil (lipid) polymerization due to high temperatures and hydrolysis. It appears that both result in the ...
0
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0answers
107 views
Changes in conductivity of CuSO4 solution after NH3 solution is added
In my high school chemistry class we are writing a lab. Originally, I wanted to measure the rate of a ligand exchange reaction at different temperatures by measuring changes in conductivity. After ...
1
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0answers
31 views
Why do some compounds without carbonyl group give positive 2,4-DNPH test?
I was performing some experiments in Chemistry Lab today in which I had to find the functional groups present in a compound.
It being a very basic undergraduate course introducing us to the ...
