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4
votes
1answer
58 views

What does it mean by non-bonding p pi orbital?

In a paper by Peng et. al.,[1] I read about the valence band maximum of $\ce{TiO2}$ consists of non-bonding O pπ orbitals ... the valence band maximum (VBM) consists of non-bonding O pπ states What ...
0
votes
2answers
69 views

Apparent inversion of oxidation state of sulfate ion using minimal basis set

It is well known that the sulfate ion has essentially no 3d-2p bonding; hence I used the minimal basis set(STO-3G) for the NBO calculation I did via Gaussian, just to check it. However, I got a ...
4
votes
1answer
103 views

Which amines show N−N coupling reaction?

We add 1 equivalent of $\ce{KCN}$ followed by catalytic reduction via Lindlar's reagent $(\ce{H2}/\ce{Pt})$ to 4-chlorobenzyl chloride (1). Verify whether the product (P) obtained will undergo an N−N ...
0
votes
0answers
60 views

Determine anion radius in FCC cell

The edge length of an FCC cell is $\pu{508 pm}$. If radius of cation is $\pu{110 pm}$, the radius of anion is? My approach: $$(2R_{\text{cation}}+2R_{\text{anion}})^2=2a^2$$ Which on simplification ...
-1
votes
0answers
47 views

How to purify and extract pure indium out of a solution

I have been searching the internet for a while now and nothing did answer my question in a concrete way. Let's say I have a solution of indium mixed with oxalic acid and possibly some other (unknown) ...
-2
votes
0answers
20 views

Can iron oxide nanoparticles form with diamagnetic surfactants?

When using charged surfactants, such as oleic acid the preparing iron oxide nanoparticles, what would result from utilizing a charged surfactant with a negative magnetic susceptibility?
-1
votes
0answers
32 views

Assessing dangers of light/radiation to gasoline/oil and its vapors?

I was thinking about precautions you if you wanted to perform visual inspections of a barrel of oil and that made me start wondering. Are there any major safety risks associated with using light ...
-3
votes
0answers
48 views

Ethylene/Propylene Glycol

Can propylene glycol be mistaken for ethylene glycol in a blood sample test using gas chromatography with a flame ionization detector?
2
votes
0answers
40 views

Does a larger bond energy in reactants mean a more exothermic reaction?

In the book "Combustion Physics" for C.K Law, page 42, it is stated that: The parameter that has the next strongest influence on [adiabatic flame temperature] $T_{ad}$ is the $C/H$ ratio of ...
0
votes
0answers
40 views

Major product in the reaction of alcohol with unsymmetrical acid anhydride

When alcohol reacts with symmetrical acid anhydride to form ester. We have the following reaction, But if the acid anhydride used is unsymmetrical how can we identify the major product? For example ...
0
votes
0answers
26 views

At equilibrium, which one of the following is always Zero? [duplicate]

At equilibrium, which one of the following is always zero? (A)∆H (B)∆S(Total) (C)∆S(System) (D)∆G° I know that at equilibrium ∆G=0, and was facing difficulty in connecting the above mentioned ...
-1
votes
1answer
36 views

Prepairing a Sodium Acetate buffer - Meaning of molarity

We have instructions to prepare a "50 mM Sodium Acetate, pH 5 solution". I am not entirely sure what does the molarity refer to in this case. Does it mean: Add Sodium Acetate salt up to 50 ...
0
votes
0answers
27 views

Side-chain Oxidation vs Oxidative Cleavage

When the above compound is subjected to acidified $\ce{KMnO4}$, can both side chain oxidation and oxidative cleavage of $\ce{C=C}$ bond occur? Or will one have priority over the other?
1
vote
1answer
28 views

Height of FCC arrangement

I have read that height of HCP arrangement is given by $\mathrm{4r\sqrt{\frac23}}$ as distance between consecutive layers is $\mathrm{2r\sqrt{\frac23}}$(in both FCC and HCP). If that is the case, then ...
2
votes
1answer
41 views

Determining ppm concentrations from food label information for ICP-OES analysis?

Overview: I am looking to determine what ppm values of trace metals are present in a particular formula while considering digestion, dilution, and detection limits for ICP-OES. For example, one ...
0
votes
0answers
4 views

With functions as functions of special coordinates in Gaussian g09 [migrated]

I would like to generate wave functions as functions of spatial coordinates (X, Y, Z) in Gaussian G09. How might I go About doing this? I am using Linux and my preferred visualization software is ...
5
votes
2answers
657 views

Materials for McBride's Freshman Organic Chemistry at Yale University

I have been looking over the online Organic Chemistry course taught by McBride at Yale and named "Freshman Organic Chemistry", 125A, which is on Itunes University. Only the lectures are ...
1
vote
1answer
40 views

Transparent material used in the movie Metropolis

This is probably a rather unusual question for this forum. The review of the movie Metropolis (made in 1926) by Roger Ebert shows what I assume is a still frame from the movie: The shield looks very ...
0
votes
0answers
31 views

What is the mechanism when 1-chloro-4-nitrobenzene reacts with NaOH?

The reaction mechanism in my textbook when 1-chloro-4-nitrobenzene reacts with NaOH is given as follows, When chlorobenzene reacts with NaOH the product formed is phenol with benzyne as the reaction ...
0
votes
0answers
36 views

Current density from overpotential

A current of $190$ mA is measure for a $2.5$ cm$^2$ electrode in contact with a solution containing M$^{2+}$/M$^{3+}$ metal ions at room temperature at a overpotential of +$180$mV. The transfer ...
-1
votes
0answers
114 views

Hypothetical Quantum Chemical code without bothering with complex numbers

I have never understood why it is required to define the wave function as a complex function. Why bothering with all of these i, with Hermitian algebra and with adjunct operators? What would it change ...
0
votes
0answers
25 views

Calculating the concentration of reactants and products in parallel reactions after a time t

A substance A reacts with a solvent B to form an intermediate product IP. The reaction is bimolecular. The conc. of the solvent is constant at $12$M. IP can then react to form the two products P$1$ ...
1
vote
0answers
29 views

Units of collisional cross-section and reactive cross-section

I haven't been able to find the units of the reactive cross-section (σ* = Pσ) online but when I do a unit analysis from the equation: $$ k = PσN_A √(\frac{8k_BT}{πμ}) e^{-E_a/RT}$$ then when plotting ...
0
votes
1answer
32 views

How to convert benzyl alcohol to 2-phenylethanoic acid?

How can we convert benzyl alcohol to 2-phenylethanoic acid? This is what I have tried. Can someone tell me whether this is correct because I am not sure about the second reaction. In my textbook it ...
-2
votes
1answer
46 views

stoichiometric crystal

I wonder if there is something like a "stoichiometric crystal"? In other words: Is it possible to have a crystal that is non-stoichiometric? I'm not interested in crystal defects but don't ...
1
vote
0answers
52 views

Determining reaction order from absorbance

A reaction is initiated in a solution which contained a dissolved component. The transmittance was measured at $\pu{240 nm}$ in a $\pu{2.54 cm}$ long cell. At $t = 0$ the transmittance was $1$. $\...
0
votes
0answers
35 views

What determines the coefficient B in the Bell-Evans-Polyani equation?

From the Bell Evans Polanyi principle, $E_a = A + B \Delta H$. How is the $B$ coefficient determined? This is my thinking: For exothermic reactions (where the transition state resembles reactants more ...
0
votes
0answers
29 views

Number of gas molecules in activated state vs normal state

I have a simple bimolecular reaction $$\ce{A + M <=>[k_2][k_1] A^* + M}\tag{1}$$ where $\ce{A}$ is a molecule which collides with another molecule $\ce{M}$. $\ce{A^*}$ is the $\ce{A}$ molecule ...
2
votes
0answers
19 views

Oxidative cleavage of alkenes by Chromic Oxide

Does CrO3 (hot concentrated or acidified like Jones Reagent) cleave alkenes and alkynes like hot conc KMnO4 would, like this reaction? If not, why not? And do any other reagents other than Ozone ...
0
votes
1answer
29 views

How does oxygen share its lone pair(solid) with two central metals in coordination compounds

I have started learning about coordination compounds recently, so do not have even respectable amount of knowledge of it. In one of the examples given in the source (μ-hydroxo-bis(pentaammine)chromium(...
1
vote
1answer
41 views

Method to remove impurities from acetaminophen synthesis experiment

I'd like to know about impurities from acetaminophen synthesis experiment. Are there any impurities produced by oxidation of p-aminophenol? If there is any impurity produced by oxidation of p-...
0
votes
1answer
58 views

How switching values of $R$, $K_p$ and $K_c$ does not alter the value of change in standard Gibbs energy? [duplicate]

$\Delta_\text r G=RT\ln \frac{Q}{K}$ If we switch $K_p$ from $K_c$, accordingly $Q_p$ will change to $Q_c$. Therefore, value of $\Delta_\text r G$ remains the same. $ΔG^\circ=−RT\ln K=ΔH^\circ−TΔS^\...
-1
votes
1answer
75 views

Why is "Carbon can form many compounds with long carbon chains" not correctly explained by "Carbon atoms can share electrons with one another"?

Why is "Carbon can form many compounds with long carbon chains" not correctly explained by "Carbon atoms can share electrons with one another"? I am a high school student just ...
-1
votes
0answers
35 views

Copper (I) nitride formula

Why is Copper (I) nitride's formula Cu3N? My periodic table says that nitrogen has a -2 state too, so couldn't it be Cu2N instead?
0
votes
0answers
19 views

Mechanism of Action of Carbachol

Carbachol (carbamylcholine chloride) is known to be a cholinergic agent. Does it work as an indirect agonist by inhibiting acetylcholinesterase, as a direct agonist of acetylcholine receptors, or is ...
-1
votes
0answers
27 views

E Z configurations of alkenes where one of the substituents is same (a ring) [duplicate]

[I dont understand how we assign priority to the c=c group which has both of its valencies satisfied with the same substituent. Should I open the ring? Even then wouldn't it be the same?]
0
votes
1answer
41 views

confusion regarding meta-cresol and phenol

when I googled the answer, i found out that m-cresol has a PKa value of 10.1 whereas phenol has 10.0. I am simply unable to use any logic to compare their strengths. We have been taught only the ...
-2
votes
0answers
21 views

Does o-chloro phenol exhibit intermolecular hydrogen bonding along with intramolecular hydrogen bonding? [closed]

Though intramolecular hydrogen bonding exist in the above compound but will it also exhibit intermolecular bonding to any extent?
0
votes
0answers
10 views

Quantifying Residual Chlorine content in ppm in a Hydrocarbon

I have a process troubleshooting application where we need to quantify the amount of residual chlorine content in a liquid Hydrocarbon sample since this chlorine is a poison for the downstream ...
2
votes
0answers
77 views

What gives natural rubber a permanent shiny finishing?

Natural rubber is made by vulcanizing latex mixed with sulphur. Commonly, the resulting natural rubber is dull instead of shiny. However, there are also products made out of natural rubber that are ...
0
votes
0answers
37 views

Cleaning used frying oil with salt water : what is the point of using salt?

In the process of making soap from used frying oil, I need to purify the oil. I filtered the cooking oil but I also want to remove the polar compounds that are formed during frying : free fatty acids, ...
0
votes
1answer
21 views

Databases for Enthalpy of Solution and Ionic Radii for Ionic Salts

I am looking to investigate the relation between experimental enthalpies of solution and theoretical enthalpies of solution calculated using theoretical equations for the lattice enthalpy and ...
-1
votes
2answers
100 views

Why does/doesn't sodium carbide exist?

(Here, I quote a question from an Indonesian undergraduate Chemistry competition: "sodium carbide reacts with water to form ethyne gas." This is the problem that caused me to ask this ...
0
votes
1answer
41 views

Reaction Mechanism for a radical ring opening

I have a radical reaction which I got from an organic chemistry lecture and was drawing the possible mechanism for it. Fig 2. shows my thought process. The I is removed making a radical and ISnBu$_3$. ...
-1
votes
0answers
30 views

Does ozone have polar bonds?

Does $\ce{O3}$ have polar or non-polar bonds? My teacher says that $\ce{O3}$ has non-polar bonds. But chem-libre texts and many other sources state that a non-polar bond has equal distribution of ...
1
vote
1answer
22 views

Reducing sugars and redox potential

I am wondering if reducing sugars are those that can act as reducing agents, and they act as such with Tollens and Fehling reaction, then what's the redox potential here? And is it a reversible ...
0
votes
1answer
20 views

Adsorption on solids - homogeneous/heterogeneous surface definition

How could we define homogeneous and heterogeneous surfaces (rigorously)? It is among my exam questions (but I could not find any definition in my textbook or on the internet). I would say the ...
0
votes
0answers
23 views

Natural preservatives of ink

Would pure compounds like thymol, carvacrol and cinnamaldehyde work as preservatives of fountain pen ink? I'm specifically interested in three properties - Prevention of growth (mostly fungal) in the ...
1
vote
0answers
43 views

How to remove starch from silicone ("Oogoo")?

Oogoo is an easy and cheap way of creating silicone rubber objects from a hand-formable putty. Basically: just mix silicone caulk with starch (I'm using acetate moisture absorbing silicone caulking ...
-2
votes
1answer
36 views

What does it mean by spatial neighbor?

What does it mean by a spatial neighbor (SN) in the case of a protein residue or protein chain? Why is it different or special as opposed to other neighbors?

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