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1answer
11 views

Purity of aluminium and experimental setup differences between Hoope and Hall–Héroult processes

Recently I was taught how aluminium is commercially extracted. The ore is first concentrated by leaching either by Bayer's process for red bauxite (impurity: $\ce{Fe2O3}$) or by Serpeck's process for ...
0
votes
0answers
7 views

Can triethylene glycol be used to remove polypropylene from the die during the glycol bath process?

We use the glycol bath die cleaning process in order to clean our die which are used to extrude materials from PBT and PET. Can triethylene glycol be used in order to clean a die containing ...
-1
votes
0answers
10 views

how to test for purity

Is there a home testing method for the purity of lgd4033? Formula: C14H12F6N2O IUPAC ID: 4-((R)-2-((R)-2,2,2-trifluoro-1-hydroxyethyl)pyrrolidin-1-yl)-2-trifluoroMethyl)benzonitrile Elimination half-...
0
votes
0answers
12 views

Which is more stable , a phenyl carbanion or a ethyl carbanion?

I came across this question in my class test and the answer given is ethyl carbanion . But as per the S character and electronegativity , the phenyl carbanion should be more stable . My teacher told ...
0
votes
1answer
23 views

Why does snow sublime even when the surrounding temperature is below 0 °C?

Snow in winter below 0 °C, still sublimed very slowly over time. If I’m not mistaken, sublimation is an endothermic process. Where is this absorbed energy coming from when the surrounding temperature ...
-1
votes
1answer
14 views

Enthalpy Changes [on hold]

0.50 g of Mg is added to a 50 mL HCl solution. The temperature increased by 5.2 degree Celsius. Calculate the enthalpy change for the reaction per mole of Mg that reacted.
-1
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0answers
16 views

Which of the following are identical?

So what i know is that when we rotate a fisher projection by 180° then we get identical compounds Going with that i think the option 1 should be correct but in the key the option 4 is given as ...
0
votes
1answer
15 views

If water freezes at 32 °F (0 °C) at sea level, then what temperature does ice melt?

If water freezes at 32 °F, what happens to that newly formed ice at that temperature? Does it start melting as soon as it’s frozen, or does it require more heat to melt again? If it does require more ...
1
vote
1answer
16 views

How is Zn not a transition metal?

A transition metal can be defined as an element that possesses an incomplete sub-level in one or more of its oxidization states. In the textbook I'm reading, it claims that zinc is not a transition ...
-1
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0answers
13 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 ( ...
-2
votes
0answers
11 views

How can i change atom color or size partially in VMD 1.9.3? [on hold]

For examples, I want that some carbons are changed to red while the other carbons are changed to blue. I don't want that changing all carbon to other color or size. Please explain to me in details.
-1
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0answers
20 views

Synthesize of N-(heptane-4-yl)-N-phenylpropionohydrazide [on hold]

I have the following question I tried to answer and I couldn't and I searched the internet and I couldn't. I appreciate any help
-2
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0answers
12 views

calculations buffer solution using pka and henderson's equations [on hold]

What is the $\mathrm{pH}$ of mixture of $\pu{5ml}$ of $\pu{0.1M}$ of $\ce{CH3COONa}$ and $\pu{4 ml}$ of $\pu{0.1M}\ce{ CH3COOH}$.If the $\mathrm{p}K_\mathrm{a}$ is 4.76? How is the $\mathrm{pH}$ ...
4
votes
2answers
164 views

Which biphenyl is optically active?

Which biphenyl is optically active? I know that it can never be 1. I don't think it will be 4 either as I read that it should be ortho-substituted biphenyl. So, when I look at 2 and 3, I can't ...
-4
votes
0answers
31 views

What software packages can be used to computationally model electrochemical reactions? [on hold]

I'm looking for software, other than COMSOL Multiphysics, which models electrochemistry (particularly electrocatalysis) effectively. Any suggestions would be very useful. I already have access to ...
-1
votes
0answers
19 views

Furniture spray recipe [on hold]

I am trying to formulate a natural furniture spray with a small amount of beeswax, olive (or mineral) oil, and polysorbate 80 and water. In order to emulsify the oils enough to spray, a large amount ...
-1
votes
0answers
10 views

is Mg(OH)2 able to remove the free PO4 3- ions produced by the hydrolysis of phenolphthalein phosphate using phosphatase

I wanted to investigate the effects of magnesium ions on preventing the end production inhibition of phosphate ions on phosphatase enzymes (from splitting phenolphthalein phosphate, PPP). My idea was ...
0
votes
0answers
19 views

Ka for reaction from tables [duplicate]

For the reaction below: NH4+ + H2O -> NH3 + H30+ I have the following values from a table to use: And in the solution manual they tell me to use the Ka for this reaction. Why is this? Why do we ...
-3
votes
1answer
27 views

Phenolphthalein and methyl orange end points comparison

In determining the solubility constant for Ca(OH)2, how does phenolphthalein end point compare with the methyl orange end points?
-2
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0answers
16 views

Ph2C=CH2 (1), PhCH=CHPh(2) , PhCH=CHCH3(3) reactivity order towards HCL [on hold]

Ph is phenyl group and according to me it is 1>2>3
-4
votes
0answers
18 views

Which is more reactive towards Grignard reagent, RCOOR or RCONH2? [on hold]

My answer is RCONH2 BUT IT IS GIVEN RCOOR WHY
-1
votes
0answers
10 views

Which plasticizers can be used in resole urea formaldehyde resin in making decorative laminates? [on hold]

I am looking for a non-glycol group, superior than Diethylene glycol.
1
vote
0answers
24 views

What apparatus is needed to get a balloon full of anhydrous carbon dioxide from solid carbon dioxide? [on hold]

I'm currently planning a research project (new to this) and we need to bubble CO2 through our reaction mixture, however we are not able to use compressed gas so have been advised to pass CO2 from dry ...
0
votes
0answers
31 views

Heat capacity calculation with temperature dependence [on hold]

I understand that when the heat capacity depends on temperature you can perform an integration. For the equation $C_p = a + bT + c T^2$: In order to compute change of entropy we have to integrate ...
2
votes
0answers
26 views

Radicals in Gaussian

I want to do a PES scan of a radical structure in Gaussian. However, I'm not completely sure how to prepare an input file. I've figured out that charge and multiplicity are 0 and 2. What I don't know ...
-4
votes
1answer
17 views

Problem from Ionic Equilibrium [duplicate]

This seems to be a pretty easy problem but I cannot understand why we do not consider the contribution of $\ce{H+}$ ions by water (water dissociates into $\ce{H+}$ and $\ce{OH-}$) and only that of $\...
-2
votes
0answers
9 views

Chemistry individual experiment to do with cosmetics [on hold]

I am assigned an individual chemistry experiment which I should topic to my liking and possibly design the experiment or personalize the experiment to some extent. I am interested in exploring the ...
-2
votes
0answers
13 views

Biosynthesis of cellular material [on hold]

Name the single most important structural tissue in (1) higher vertebrate animals and (2) woody plants
-2
votes
0answers
19 views

The question is about chemical equilibrium [on hold]

The reaction of ... Is one of the instantaneous reactions. (Mg strip in HCl solution, silver nitrate with sodium chloride, both of the two answers)
1
vote
1answer
27 views

How much CO2 is emitted by burning coal to produce 1 kWh of energy

I'm a little embarrassed to ask this question at this stage of the climate game but, in searching, I seem to get contradictory answers. For example, here: https://www.eia.gov/tools/faqs/faq.php?id=73&...
1
vote
2answers
48 views

how can carbon dating even work? Its at atomic level!

I am a homeschooling parent, so pardon me asking stupid questions. Everywhere I read, it is said carbon based lifeforms eat carbon and after their death that atom starts a decay. But what I cannot ...
-1
votes
0answers
23 views

Energy generation [on hold]

question 3: Energy generation is fundamental to living cells. Without it, no living tissue could be constructed - transport, polymer synthesis, gene expression and response to the environment would ...
-2
votes
1answer
38 views

How can i convert .gjf or .chk file to .wfn file? [on hold]

Please explain to me in details. I can't understand corresponding contents in manual.
1
vote
0answers
24 views

Electrons and Atomic Mass

Is the mass of electrons covered when talking about atomic mass. For example, the mass of Carbon is $12.011\space\text{amu}$. If this is including the mass of electrons (assuming the atom is neutral) ...
4
votes
2answers
60 views

Is (2R,3S)-3,4-dimethylpentan-2-ol feasible to be dehydrated with POCl3 and pyridine?

I was given a problem of reaction between (2R,3S)-3,4-dimethylpentan-2-ol and $\ce{POCl3}$ and pyridine. I know that $\ce{POCl3}$ will be attacked with hydroxyl group and the hydrogen on hydroxyl will ...
0
votes
0answers
35 views

Is Radioactive Mineral Kit safe for classroom? [on hold]

I found in our stock room a set of radioactive minerals from Ward’s Scientific. The set looked old and had no information enclosed. Upon contacting the company, I was told that the set had been “...
2
votes
1answer
51 views

Atomic emission spectrum assumption n_f = 3

It's a standard question on the atomic emission spectrum. An atomic emission spectrum of hydrogen shows three wavelengths: 1875 nm, 1282 nm, and 1093 nm. Assign this wavelengths to transitions in ...
-2
votes
0answers
22 views

How does changing parameters in orientation factor equation affect K?

I am bit confused about orientation factor. According to equation $$K = pz_0\mathrm e^{-E_\mathrm{a}/RT}$$ $K$ is equilibrium constant, $p$ is collision orientation, $z$ is collision frequency and $...
1
vote
1answer
57 views

Oxidation States of D Block Elements

These might be basic question but they are quite confusing to me? If $\ce{Sc+}$ doesn't exists, why does $\ce{Ti^{2+}}$ exist? on the similar account why does this trend increases at first( till Mn)...
0
votes
1answer
43 views

What is the white powder that I have extracted from cinnamon?

In Advanced higher chemistry, I am extracting cinnamaldehyde using this procedure- https://www.flinnsci.ca/api/library/Download/ba6ab218508047ea843bb0d9e580be16 . After evaporating the hexane, instead ...
1
vote
2answers
44 views

Entropy as an intrinsic property of matter

I would like to ask how we can see entropy as an intrinsic property of molecules, namely as something depending also on their geometry (and not only as gross disorder). Is this what is called the "...
1
vote
0answers
19 views

Copper plating with switched anode and cathode [on hold]

Please help! I was working on a mock research project/lab for my chemistry class testing the rate of electroplating of copper vs. voltage. I had copper and nickel electrodes and .1M copper sulfate ...
0
votes
0answers
24 views

How to prevent feasibility of intermolecular attack of 1,2-diol?

I was given a problem that requires me to synthesize (1R,2R)-2-methoxycyclohexanol from cyclohexene. I tried it with syn-hydroxylation of alkene $\pi$ bond with $\ce{OsO4}$ and NMO then directly ...
-1
votes
0answers
25 views

Robinson annulation mechanism [on hold]

How do I start a mechanism to find the product? I started by deprotonating the alpha proton but I don’t know what’s next
-1
votes
0answers
12 views

What's the percentage of Thallium in those low temperature thermometer? [on hold]

Also, what's the solubility and volatility of that compound, and how toxic it is?
1
vote
1answer
36 views

Calculate voltage, cost and time of nickel coating

To nickel with a bath of $\ce{NiSO4}$ a cathodic current of $\pu{0.3 A/cm2}$ is applied with a square plate of side $\pu{5 cm}$ is used to nickel a certain substrate. Due to the formation of $\ce{H2}$ ...
8
votes
2answers
680 views

What is the difference between chemical equilibrium and dynamic equilibrium?

Is chemical equilibrium and dynamic equilibrium the same thing? Both point to the reversible reactions and no net changes in the concentrations of product and reactant. Dynamic equilibrium from ...
1
vote
0answers
47 views

Determining heat capacity of gasses

I need a little help on answering a question which popped into my head while I was reading about gas laws: Suppose that I have three canisters, each holding a different gas of unknown identity [...
2
votes
1answer
51 views

Organic Chemistry - Effect of methyl substituent in Aromatic Substitution via Benzyne

The following reaction has been taken from my study material. This shows that the benzene ring is undergoing a nucleophilic aromatic substitution via benzyne mechanism (presence of a strong base like $...
-3
votes
1answer
47 views

Order of paramagnetism among nitrogen, oxygen, aluminium and calcium [on hold]

Which of the following arrangements show a decreasing order of paramagnetism? a.) N > Al > O > Ca b.) N > O > Al > Ca c.) O > N > Al > Ca d.) O > N > Ca > Al The answer was b. Although I ...

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