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8
votes
2answers
424 views

Software for generating a lattice from a unit cell for molecular crystals?

I am looking for a software package which can take a unit cell (and lattice parameters, etc.) and from that generate a crystal lattice. Ideally it will have functionality for orthorhombic, hexagonal, ...
2
votes
1answer
71 views

How to calculate the number of protons in a sphere given the volume and the pH?

The spherical radius of a nano-droplet of a solution ($\mathrm{pH}$ of which is $6$) is given as $\pu{20nm}$. I can find the molar concentration of $\ce{H+}$ and subsequently the number of $\ce{H+}$ ...
-1
votes
0answers
26 views

Different Lewis Structures for Sulfate [duplicate]

I was trying to draw the Lewis structure of Sulfate $\mathrm{SO_4^{2-}}$ that I realized that both of these structures are possible: The first one has two double bonds and two dative bonds while the ...
-1
votes
1answer
18 views

Chemical equilibrium [duplicate]

When calculating equilibrium constant with partial pressures if there is a solid involved should we consider it in the total number of moles in mole fraction?
2
votes
1answer
79 views

How is antioxidant activity of carotenoids determined?

I am doing some research regarding carotenoids and beta-carotene. After extracting the sample, I have not been able to find a way to measure antioxidant activity of beta-carotene. I have $\pu{0.1mM}$ ...
2
votes
1answer
162 views

Show the acid nature of hydrogen sulfide

We are studying the chalcogens at school. I should prove (show) the acid nature of $\ce{H2S}$ by writing two chemical interactions. I am really sorry if the terms I am using aren't the right ones. It'...
-1
votes
1answer
57 views

Confused on how to draw cis-[Ni(H2O)4(NH3)2]Cl2 [closed]

I got a question on my practice exam telling me to draw cis-diamminetetraaquanickel(II) chloride, but I'm not sure on how to place the two $\ce{Cl}$ atoms.
2
votes
1answer
79 views

How can one determine an atomic mass with high accuracy using gravimetric analysis?

In the Wikipedia article on gravimetric analysis it is said that gravimetric analysis was used to determine the atomic masses of many elements in the periodic table to six figure accuracy. There are, ...
1
vote
1answer
38 views

Calculating the Ionic strength of sodium acetylsalicylate

With the addition of aqueous NaOH to an aspirin solutions in water the reaction will yield products of sodium acetylsalicylate and water. I would like to measure the amount of sodium apsirin formed ...
-1
votes
0answers
20 views

Why methaemoglobin is green? [closed]

Haemoglobin (Hb) in air will oxidize to MetHb with darker color (by O2). But in alpha-hemolysis (which result in formation of MetHb by hydrogen peroxide) in agar test will appear with green color ! I ...
2
votes
0answers
12 views

Acidic strength of phenol derivatives

While comparing the strengths of o-nitrophenol and p-nitrophenol, p-nitrophenol is found to be more acidic. The reason I studied for this is $\ce{H}$-bonding in o-nitrophenol which makes the acid more ...
1
vote
1answer
37 views

Reduction of amides with lithium aluminium hydride [closed]

Since $\mathrm{p}K_\mathrm{a}$ of primary amides are close to alcohols, will there be an acid-base reaction between amides and $\ce{LiAlH4}$ besides reduction?
-1
votes
1answer
34 views

Characteristics of Isotopes [closed]

I'm currently applying information theory to physics, and have begun considering the nature of isotopes, and in particular, how much information is contributed to the properties of an element by its ...
1
vote
0answers
25 views

Displacement by more electropositive metal in non aqueous environment

The more electropositive element should displace metal from it's salts' solution. This can be seen in reaction of copper salts with iron. But, if you try using for example potassium metal as the more ...
1
vote
1answer
47 views

Determining structure from C-NMR spectrum, is my answer correct?

Determine the structure of the compound whose spectral data is given below and explain your reasoning (5 marks for structure, 15 marks for reasoning). The peak at 7.27 ppm does not belong to the ...
-1
votes
0answers
20 views

Calculate pH of borax-boric acid buffer solution? [closed]

In a recent experiment I made a borax-boric acid buffer solution by dissolving 9.535 g of borax in water and adding 92 ml of 0.1 M HCl. The pH of this solution was given as 9.00. I then took 20 ml of ...
0
votes
0answers
28 views

What is the order of [H2SO4] with regards to the reaction H2SO4 + CaCO3?

What is the relationship between the concentration of sulfuric acid and the rate of reaction of $$\ce{H2SO4(aq) + CaCO3(s) ⟶ H2O(l) + CO2(g) + CaSO4(aq)}$$ in the rate law: $$\mathrm{rate} = k[\ce{...
3
votes
2answers
60 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
vote
0answers
36 views

Why London force dominates in Alkyl Halides

Why London Force is greater than dipole-dipole interactions in Alkyl Halides? As we know that most of the time London force is weaker than other forces. Then why in this case it's not so? ...
-1
votes
0answers
36 views

Food oxidation (browning) and metal ions

I'm interested to better understand how foods oxidize when they have been cut down with a ceramic knife (other than a traditional steel one) i.e. browning of a sliced apple In particular, I read ...
1
vote
0answers
28 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?
0
votes
1answer
66 views

Which chemical is used in drunken driver test?

Which chemical is used in drunken driver test? Acidified K2Cr2O7 KMnO4 Chromyl Chloride H2O2 On searching on Google, I got the answer as option 1, acidified potassium ...
1
vote
1answer
38 views

What is a material more easily cut than shattered? [closed]

I'm currently developing a sci-fi concept for animation which partially involves a typical "the earth has been overrun by XYZ" scenario. One of the ideas for XYZ we're thinking of is a species of ...
0
votes
1answer
50 views

Mechanism of Reaction of Bleaching Powder with Water [closed]

In this site https://www.askiitians.com/forums/Organic-Chemistry/21/41258/haloalkanes.htm, the reaction of bleaching powder with water is given as: CaOCl2 + H2O ----> Cl2 + Ca(OH)2 But I don't ...
-1
votes
1answer
51 views

Schrödinger wave function for 3s orbital of hydrogen atom [closed]

I am unable to understand what these terms in the wave function represent and how to solve it. For 3s orbital of hydrogen atom, the normalised wave function is $$Ψ_\mathrm{3s} = \frac{1}{81\...
0
votes
1answer
75 views

R/S chirality question

Consider [(1⁠S,2⁠S,4⁠S)-bicyclo[2.2.1]hept-5-en-2-yl]acetic acid: (Source: http://www.chemspider.com/Chemical-Structure.22823922.html) According to the chemspider nomenclature, this has three S ...
-2
votes
1answer
44 views

Why is 1,2-diiodoethane unstable? [duplicate]

Diiodoethane is a product of the reaction between glycol and $\ce{PI3}$. Why is 1,2-diiodoethane unstable?
2
votes
1answer
36 views

Reference request on formate potash process

Wikipedia article on Potassium Formate mentions a so-called "formate potash process" for production of potassium, presumably referring to elemental metal. Concise encyclopedia chemistry by Mary ...
0
votes
0answers
37 views

Hydronium ion concentration to compare pH values

I'm having a bit of trouble with this question: Which has a higher $\mathrm{pH}$ value, $\pu{0.001 M}$ $\ce{HCl}$ or $\pu{0.1 M}$ $\ce{CH3COOH}$ $(K_\mathrm{a} = \pu{1.8E-5})?$ I have calculated ...
0
votes
1answer
28 views

Question about the setting of DFT (Density Function Theory)-NEB (Nudged Elastic Band) calculation

I'm attempting to calculate Mg ion vacancy migration inside Pyrope unit cell. System has total 159 atoms, beginning and end geometry is optimized. For intermediate image, I'm using one coordinate that ...
0
votes
0answers
43 views

Validity of Maxwell-Boltzmann distribution for solids [duplicate]

Suppose there is a solid made of avogadro number of, say, aluminium atoms. This solid is kept at 273 K. According to Maxwell-Boltzmann distribution, all the particles or atoms will not have the same ...
7
votes
3answers
329 views

Identify the structure of the compound (C3H5NO) given its NMR chemical shifts

I am trying to figure out the structure of the compound $\ce{C3H5NO}$ given just the following data from the 1H NMR spectrum: $\delta 5.8 ~ \text{(singlet, 1H)}; \delta 6.2 ~ \text{(triplet, 2H)}; ...
2
votes
0answers
59 views

Oxidation state of chlorine in ClO

Today, I had a friendly debate with my friend on what should be the oxidation state of $\ce {Cl}$ in the chlorine monoxide radical. I took the view that it should be $\ce {+2}$ while he took the view ...
-1
votes
1answer
53 views

Can a gas have a boiling point?

For each of the following pairs, choose the member with the lower boiling point. Explain your reason in each case. HI(g) or HCl(g) If they were both aqueous solutions, I would know that HCl has ...
0
votes
1answer
42 views

How does solution which electrodes are immersed in effect electrode potential?

There was this question I had to do on which went like "which all metals can we not extract using electrolysis from aq soln" the answer involved the effect of solvent on electrode potentials, can ...
1
vote
0answers
25 views

Is the reaction of anhydrous aluminium(III) chloride and anhydrous ethanol reversible?

I'm planning an experiment that I'll do in silico in the near future, and one of the steps involves the extraction of the $\ce{AlCl3 · C2H5OH}$ adduct without any water in it. Can the ethanol be ...
0
votes
1answer
43 views

Why polyethylene (PE), wool (polyamide) and cotton (cellulose) burnt with different smells, while they just product CO2 (and N2)?

Both PE and cotton produce CO2, but they distinctly have different smells while being burnt (Burning PE has smell of candle wax, while burning cotton’s smell is like burning leaves). Wool produces CO2 ...
-1
votes
1answer
24 views

Is it possible to convert carbon soot/ black carbon in mg to CO2-equivalent? If so, how?

Since global warming is expressed in terms of carbon emissions or CO2 equivalent, can the short lived carbon soot/ black carbon that is produced from incomplete combustion be expressed in terms of CO2 ...
0
votes
0answers
20 views

Does Coagulation depends on nature of Electrolyte?

I am not talking about Hardy Schulz Rule . Suppose if i add an electrolyte to a colloidal solution. If that electrolyte contain same ion that of colloidal particle due to preferential adsorption is ...
0
votes
0answers
74 views

How can you use indicator titration to determine the pH of a complex solution like ocean water if at all

Could you measure the pH of ocean water by using a strong acid-weak base titration? I was thinking that you could set up a standard titration with ocean water as the "unknown", and drip the known HCl ...
0
votes
0answers
26 views

Sigma bond by combining two p orbitals

If I combine two p orbitals in such a way that they form σ bonds, which linear combination will represent bonding and antibonding? My work on this problem: $$ \begin{align} &\text{Bonding:} &...
1
vote
0answers
28 views

Reaction with ethyl chloroacetate and potassium carbonate

I am carrying out a reaction using ethyl chloroacetate, potassium carbonate in acetone for a compound containing $\ce{-NH}$ group. So, the substitution will be at $\ce{-NH}$ position. I have tried ...
2
votes
1answer
85 views

High errors in frontier orbital energy calculation using DFT

In a recent paper by Faber et . al., Mean Absolute Error and DFT (B3LYP) error (relative to the experiments) for 9 properties of QM9 dataset molecules has been reported. \begin{equation} \begin{array}...
6
votes
1answer
77 views

Are all stable Xenes (graphene-like 2D honeycomb sheets) buckled?

background: Per this abstract Silicene, germanene and stanene are part of a monoelemental class of two-dimensional (2D) crystals termed 2D-Xenes (X = Si, Ge, Sn and so on) which, together with ...
5
votes
0answers
43 views

What is tetrasulfur like? Why is there so little experimental information about it?

Phys.org's How sulfur helped make Earth habitable before the rise of oxygen says Mapping the bonds and vibrational modes of molecules containing sulfur isotopes is helping to shed light on the ...
-1
votes
2answers
86 views

What are the chemical Tests and/or reactions to distinguish propanone from butanone? [closed]

Is there any series of chemical reactions that will help in distinguishing propanone and butanone? A simpler series of reactions or tests would be optimal. I know it's easy to distinguish and possibly ...
2
votes
0answers
33 views

What is the name of the glyoxal radical after removing two hydrogen atoms?

What is the name of the radical that results from removing two hydrogen atoms from glyoxal ($\ce{CHO-CHO}$)? It has a roughly this structure: $$\ce{O=C^.-C^.=O}$$ It is an important intermediate in ...
0
votes
1answer
41 views

Photosynthesis-Equation [closed]

Everyone knows the simplified photosynthesis-equation from school: $\ce{6CO2 + 6H2O -> C6H12O6 + 6O2}$ Most people assume that the carbondioxide is being split into carbon and oxygen during ...
-1
votes
1answer
36 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 ...
0
votes
1answer
25 views

Standard Reduction Potentials and Electropositivity

I was looking through a table of standard reduction potentials and the trend seemed like it correlated with electropositivity. Is it reasonable to qualitatively compare two metals to see which has a ...

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