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1answer
25 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 ...
5
votes
0answers
43 views

Can a per-acetylated sugar anomerize?

So I have a question concerning a reaction mechanism for the reaction below. I know for certain that I get the alfa anomer, but I can't explain it. When I draw out the mechanism it doesn't make sense ...
-2
votes
0answers
30 views

Gold and gold oxide redox reaction in water [closed]

Can anyone tell me if a redox reaction of gold or gold oxide will occur in water around body temperature? I'm trying to figure out a redox reaction for two metals with saline being the conductive ...
-1
votes
0answers
34 views

I wonder if the molecule coohcocooh exists and what is the Ka [closed]

If you could insert CO in between the COOH of oxalic acid. Tack
1
vote
0answers
27 views

How many times should I run a solvent extration experiment through?

For advanced higher chemistry project, I am extracting cinnamaldehyde from cinnamon via first steam distillation and then solvent extraction using hexane. I'll be adding sodium chloride to the water/...
5
votes
1answer
75 views

pKa of phenols using UV-Vis spectroscopy

I have done an experiment where I dissolved four different substituted phenols in acidic, basic, and buffer solutions, and recorded the UV-Vis spectra for each. I'm supposed to pick a wavelength where ...
1
vote
1answer
16 views

Rate of reaction- Arrhenius equation [closed]

Can the Arrhenius equation be used if the reactants are in the solid state and if I can use it for any state, how do I do so?
-2
votes
0answers
16 views

Equivalence concept [closed]

When excess of CaCO3 is treated with 100 ml of HCl solution.The CO2 gas obtained was found to be 1.12 l (at N.T.P).What is the Normality of HCl?
1
vote
0answers
52 views

What is the pH and pKa relationship of LaCl3 in water and its precipitant La(OH)3?

In light of this question and its answers, I hope to get some insights into the $\mathrm{pH}$ of $\ce{LaCl3}$ in water and its $\mathrm{pH}$ relationship to $\ce{La(OH)3}$ precipitant's $\mathrm{p}K_\...
1
vote
0answers
22 views

Dissolving plastic resin without damaging aluminium surface

I have an aluminium surface covered with some plastic, which I intend to dissolve in order to clean the surface. On the note for the plastic I have applied, it says that it contains the following: 2-...
-3
votes
0answers
53 views

High temperature acids

Some of the proton production of an acid happens due to temperature and some of the proton production of an acid happens due to quantum tunnelling.But if we increase the temperature a lot the proton ...
-3
votes
0answers
39 views

Stability of oxohalogen species

Why the higher oxides of a halogen are more stable than the lower ones? I know that the stability order of oxides of chlorine is $$\ce{HClO4} > \ce{HClO3} > \ce{HClO2} > \ce{HClO}$$ But I ...
1
vote
1answer
67 views

The “nose” of the periodic table [closed]

My teacher said that on the periodic table there is a "nose" formed by Al, Zn, Ag, and Cd. She said that they are all fixed charged (+3, +2, +1, and +2 respectively), and said that if I write them in ...
-2
votes
0answers
33 views

Why does atomic spectrum of calcium obey bohr model?

We know that Bohr model can only define the atomic spectrum of single electron species.But during flame test,orange rays are emitted when calcium is heated.Our chemistry teacher taught its theory ...
-1
votes
0answers
29 views

Need a container filled with gas phase anions (negatively charged gas molecules/particles) for an experiment [closed]

Does this even exist? How could I get it? Could I make it? I know that most gas molecules/particles have an overall neutral charge. But I need gas phase molecules with an overall negative charge (i.e ...
0
votes
0answers
23 views

Low Spin vs High Spin Ligands [closed]

Is Fe(S2O3)2(H2O)2 a high spin or low spin complex? Fe has a charge of 2+. I can't find S2o3 in the stoichiometric series for crystal field theory, and I am new to crystal field theory, so I don't ...
-1
votes
1answer
15 views

Why does the metallic bond between the atoms become weaker down the group 1 elements? [closed]

Is it related to the electron arrangement of the elements?
-1
votes
0answers
23 views

Analysis of a partial structure as opposed to a complete molecule [closed]

Hello, I have this question, and I could calculate the valence electrons, etc. for the shown structure, but it says that this is a "partial structure". Our class is behind because several were ...
2
votes
1answer
28 views

AX Spin system ordering

I would like to ask a question about the ordering of the $\ce{X}$ spins on the right hand side of an $\ce{AX2}$ energy diagram. I was given the diagram here below: and asked to evaluate why this ...
-1
votes
0answers
18 views

Is there a solution which can remove pesticide residue on fruits and vegetables, yet not be harmful to humans? [closed]

Is there a solution which can remove pesticide residue on fruits and vegetables, yet not be harmful to humans? I want to test different home-made solutions and their effects on the pesticide residue ...
0
votes
0answers
23 views

Why does 50/50 isopropyl alchohol and water mix evaporate faster than isopropyl alcohol? [closed]

Today I did a lab and I took three thermometers for Logger Pro and then dipped them each in a liquid for 3 min (one is isopropanol, one in water and one in a mixture of 50/50). When I took them out ...
-2
votes
0answers
13 views

Resonance in chemistry and its cause? [closed]

Can someone please explain what actually is resonance in chemistry and why is this concept used in chemistry to explain stability of organic compounds?
-1
votes
0answers
15 views

Original reference of multiplicative coupled equilibria [closed]

Can I know what is the peer-reviewed reference behind the multiplicative nature of two equilibrium constants of two reactions that are additive? Example:
0
votes
1answer
28 views

What determines the atom or molecule that receives electrons during oxidation?

I'm no chemist, so bear with me. From my understanding, the reason metal oxidation occurs is because the metal is losing electrons to the oxygen ions in the air; and that an ion is an atom or ...
2
votes
2answers
106 views

Is PCl5 really trigonal bipyramidal in shape?

We know that the structure of $\ce{CH4}$ is tetrahedral, and not planar tetragonal, as a tetrahedron enables maximum distribution of $\ce{H}$-atoms in space, as they repulse from each other. This is ...
1
vote
2answers
44 views

Do colligative properties depend on the number of solute molecules?

Colligative properties are properties that are affected by the number of solute molecules dissolved in the solution. True or false? I think the statement is false, and the correct one should use "...
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 ...
0
votes
1answer
35 views

Can Michaelis-Menten constant be zero in the Michaelis-Menten Equation, or is this a non-zero constant? [closed]

Can Michaelis-Menten constant be zero in the Michaelis-Menten Equation, or is this a non-zero constant? I am applying the equation in epidemiology so I wanted to assume that it is zero but I am not ...
-1
votes
1answer
85 views

What happens when Ar and HCl are mixed at 77 K? [closed]

So our teacher asked us a simple question in the classroom: What happens when Ar and HCl are mixed at 77 K? and no other information was given. We replied various possible answers for that such ...
-2
votes
0answers
22 views

Why does the metallic bond become weaker but the van der Waal's forces become stronger as the atomic radius increases? [closed]

I just learned about the periodic table of elements. I was wondering what differences between van der Waal's force and metallic bond are. I'm just a rookie in chemistry. Can anyone please correct me ...
7
votes
3answers
2k views

Why does radiocarbon dating only work in nonliving creatures? [duplicate]

I understand how carbon dating works, though I do not understand why it doesn't happen while a creature is living. Because while we are alive we still have carbon 14 in us, so shouldn't it work?
-1
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0answers
38 views

What is the proper IUPAC name for the structure shown below? [closed]

I figured the longest chain is 7, root name is Heptane. Side groups are Ethyl and methyl. Ethyl has the lowest combonation of (2, 5 ) . Would it be 4-ethyl-2,5-dimethylheptane?
-2
votes
0answers
21 views

What would happen if you placed water in two containers with the same amount, but one of the containers has a cover? You'd leave them overnight [closed]

this is a question I yearn to know, as due to the fact that one of my teachers didn't quite explain how and why this was connected to out topic.
-2
votes
0answers
51 views

Energy loss or gain

When Na forms Na+ it gains energy. On forming Na+ it has electronic configuration of neon which is an inert gas. Inert gases have least energy as compared to the other elements. So having inert gas ...
-2
votes
0answers
14 views

How can I create process-able receptors for AutoDock Vina? [closed]

I am having issues creating pdb files that can be viewed and converted into pdbqt files using AutoDock Tools. Amber MD was used to generate average structure pdb files (this was done by another person)...
-1
votes
1answer
25 views

How does the molarity of the electrolyte solution affect the mass of copper formed on the cathode in the electrolysis of CuSo4? [closed]

I'm struggling with a chemistry assignment, as I have to calculate the efficiency of an electrolysis solution, where I am given the Molarity of the electrolyte solution. Does anyone know how to ...
-3
votes
0answers
19 views

Application of general binding equation in ITC experiment [closed]

A hypothetical protein $(\ce{M})$ binds a ligand $(\ce{X})$ with $1:1$ stoichiometry, a dissociation constant, $K_\mathrm{D} = \pu{1 μM},$ and binding enthalpy $ΔH = \pu{-5 kcal/mol}.$ Suppose an ITC ...
0
votes
0answers
38 views

Why is [NiCl2(PPh3)2] tetrahedral and [NiCl2(PMe3)2] square planar?

I'm confused here since PPh3 is a strong field ligand and would try to make the molecule square planar but is bulky and would tend to adopt tetrahedral geometry to minimise sterric hindrance. And why ...
0
votes
2answers
70 views

Obtaining mercury from mercury(II) nitrate

I was thinking about obtaining mercury from mercury(II) nitrate. Is it possible? I've tried putting chunks of Fe into it, I've got the logic from the voltaic table (where Fe is on the left side of Hg, ...
-2
votes
0answers
20 views

Order of reaction in adsorption process

(1) $\ce{PH3(g) <=>[W]PH3(adsorption)->[W]P(s) + 3/2 H2(g)}$ The decomposition of phosphine on tungsten surface at low pressure is a pseudo first order reaction. This is because the rate of ...
-2
votes
0answers
20 views

Melting Wood On A Serious Note [duplicate]

I wanted to ask this question for a long time. The question is Is it possible to completely melt wood(Literally change it to liquid) All I've been getting is contradictory answers. Help please!
4
votes
1answer
160 views

Definition of NMR peak

In NMR a spectrum consists of noise and peaks. While steps, such as repeated scans or smoothing of the spectra can reduce noise some still remains. As such one step usually taken is to bin the data so ...
1
vote
0answers
22 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 ...
2
votes
1answer
53 views

Kohlrausch Law and conductivity

Im writing up a lab report at the minute and part of it concerns ions in solution and how they affect conductivity. I've been doing lots of reading and I think ive got the grasp of most of it, but its ...
-2
votes
0answers
33 views

Glassware identification [closed]

These two pieces of glassware came from an estate sale and are believed to date from the fifties, but I have no idea what they are. The spherical one would need offset stopcocks maybe like those used ...
1
vote
0answers
31 views

Thermochemical data for thiocyanatoiron(III) ion

I am currently writing a lab report about the formation constant of $\ce{FeSCN^2+}.$ All I could find online was a formation constant at $\pu{25 °C}$ $(890),$ which was 70% higher than the ...
0
votes
0answers
19 views

Convert to NASA polynomial format for chemical kinetic calculations

I have calculated thermodynamic properties of a metal oxide through DFT calculations, I want to convert it to NASA polynomial format and use those thermodynamic properties along with rate constants ...
1
vote
0answers
36 views

Charactaristics of Certain Hydroxyl Protecting Groups

I have been reading through Philip J. Kocienski's book Protecting Groups to try to better understand some of the characteristics of hydroxy protecting groups. I am looking to understand the ...
1
vote
0answers
16 views

Interpretting relative probabilities based on Boltzmann's probability distribution?

I understand that Boltzmann's probability distribution gives the relative probability of one microscopic state in comparison to the other (P1/P2) but I don't know how exactly to understand this. For ...
-1
votes
0answers
23 views

Find the concentration of each substance at equilibrium

I have a question that asks me to find the concentration of each substance when the equilibrium of the reaction is established: We pour $\pu{0.02L}$ of $\ce{Ba(NO3)2}$ ($\pu{0.1 mol/L}$) into $\pu{...

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