# All Questions

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### pH and pKa relationship of LaCl3 in water and its percipient La(OH)3

In light of this question and its answers, I hope to get some insights into the pH of LaCl3 in water and its pH relationship to La(OH)3 percipient's pKa? What can be done in order to prevent LaCl3 ...
5 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-...
10 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 then the ...
7 views

### I was reading a book on halogen and came across below, plz help [on hold]

Why the higher oxides of halogen are more stable than lower oxides??
12 views

### The “nose” of the periodic table

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 ...
15 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 ...
17 views

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

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 ...
9 views

### Low Spin vs High Spin Ligands

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 ...
11 views

### Why does the metallic bond between the atoms become weaker down the group 1 elements?

Is it related to the electron arrangement of the elements?
15 views

### Analysis of a partial structure as opposed to a complete molecule

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 ...
6 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 ...
14 views

### Non constant Michaelis constant in Michaelis-Menten kinetics

For some reasons, I have to do with more or less actual chemistry these days and need some help. To be precise, I have been giving the task to supervise some enzyme kinetics. But as this has nothing ...
15 views

### Calculating the pH of a mixture of glycine and sodium hydroxide

What is the pH of a total 500 ml solution of 0.20 mol of glycine and 0.025 mol of NaOH? I believe the pKa of the amino group is approximately 9.6; the pKa of the carboxylic acid group is 2.8. Are ...
9 views

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

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 ...
20 views

### Why does 50/50 isopropyl alchohol and water mix evaporate faster than isopropyl alcohol?

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 ...
13 views

### Resonance in chemistry and its cause? [on hold]

Can someone please explain what actually is resonance in chemistry and why is this concept used in chemistry to explain stability of organic compounds?
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### Original reference of multiplicative coupled equilibria [on hold]

Can I know what is the peer-reviewed reference behind the multiplicative nature of two equilibrium constants of two reactions that are additive? Example:
23 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 ...
58 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 ...
28 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 "...
749 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 ...
31 views

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

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 ...
71 views

### What happens when Ar and HCl are mixed at 77 K? [on hold]

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 ...
21 views

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

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 ...
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?
31 views

### What is the proper IUPAC name for the structure shown below? [on hold]

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?
20 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 [on hold]

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.
40 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 ...
20 views

### Recrystallization [on hold]

Briefly describe using a suitable example, how in laboratory, you could purify an organic compound (which is suitable in hot water, but not in cold water), from a mixture of 2 contaminants, one of ...
12 views

### How can I create process-able receptors for AutoDock Vina?

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)...
21 views

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

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 ...
13 views

### Which of the following has an heat of formation equaling zero? [on hold]

a. H b. N c. O d. F2 e. none of the above
26 views

### Mixture Question [on hold]

The extent of ionization of NaCl and MgCl2 in water is 80% and 50% respectively. If a sample of water has 5.85% (w/w) NaCl and 9.5% (w/w) of MgCl2, ( Kb = 0.52Kkg/mol) Does the mixture acts as an ...
19 views

### Application of general binding equation in ITC experiment [on hold]

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 ...
23 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 ...
62 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, ...
14 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 ...
16 views

### What chemicals are in borax that turn pva glue into a solid [on hold]

When making slime< we all know that contact lens solution and borax are the common chemicals used to activate the slime, but what specific ingredients are contained in this chemical? And ultimately,...
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!
152 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 ...
14 views

### Solubility Levamisole (100 mM) [on hold]

My question is this: I want to dissolve levamisole in distilled water. The solubility of levamisole in water is 100 mM. So when it is calculated as the classical calculation, m (gr) = molecular weight ...
17 views

### If you reflux glacial ethanoic acid and ethanol (with sulfuric acid) is the reaction color yellow or clear? [on hold]

I am trying to conduct an esterification reaction and heating glacial ethanoic acid and ethanol under reflux (with sulfuric acid as a catalyst). However, after I heat it around 15-20 minutes the ...
14 views

### how to make gel based air freshener scent last longer? [on hold]

I am the CEO of a small manufactory specialized in producing air freshener and absorber products. right now one of our mail products is air gel which a gel based aroma, I am looking for a trick to ...
19 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 ...
38 views

### KineticTheoryofGasesquestion [on hold]

More than one correct: The isothermal compressibility is a function defined by Z = -(1/V)(dV/dP). a)Z for ideal gas > Z for real gas when T > a/(bR) b)Z for ideal gas < Z for real gas when T > a/(...
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### Solubility of Borax penta hydrate in water at various temperatures [on hold]

Solubility of Borax penta-hydrate in water at various temperatures from 20 to 100 Deg. Centigrade?