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1
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1answer
6k views

What is an equivalent?

I want to know what is an equivalent and how is it different from equivalent mass. How to calculate and why is it used in chemistry for knowing concentration?
3
votes
2answers
2k views

Reduction of terephthalic acid to an alcohol (or phenol?)

I want to convert terephthalic acid (TPA) to an alcohol (however I think the correct term would be "a phenol"). I've read that lithium tetrahydridoaluminate ($\ce{LiAlH4}$) can produce an alcohol ...
2
votes
1answer
146 views

Do the compounds NaₓIrO₂ and NaOsO₂ exist?

Based on some physics background, I want to know whether have scientists synthesized these two materials: $\ce{Na_{$x$}IrO2}$ and $\ce{NaOsO2}$ in the lab, if so, what properties do they have? I ...
3
votes
1answer
1k views

What's the difference between mass spectrometry, mass spectroscopy, and mass spectrography?

It seems that the terms mass spectrometry, mass spectroscopy, and mass spectrography are mostly used like synonyms. Is this correct? Or is there a difference?
3
votes
4answers
843 views

How to read a given chemical formula?

I'm trying to read this chemical formula but I'm a bit confused. I'm hoping that someone could help break this down for me to explain what the various parts mean. Someone purchased epigallocatechin in ...
5
votes
2answers
568 views

Can lye be extracted from bamboo ash?

I know that the best source of lye is hardwood. A brief search tells me that Bamboo is considered a hardwood of the monocotyledon variety. I've done a lot of searching to find this answer, but I can't ...
5
votes
1answer
1k views

How to predict a COSY NMR spectra for an AMX spin system?

Does anyone know how to draw (predict) a hypothetical COSY NMR spectra for AMX spin system (the spin of A M X nuclei is 1/2)?
1
vote
1answer
199 views

Ideal gas derivations

For an ideal gas, how can someone obtain this: $$ \bar{V}dP = RdT- P \bar{dV}$$ from which it can de deducted, that for a constant temperature $$ \frac{dP}{\bar{dV}} = -RT $$
2
votes
1answer
311 views

explain the reaction mechanism [duplicate]

$\ce{ROH + NaBr + H2SO4 -> RBr + NaHSO4 + H2O}$ What is exactly the reaction mechanism. Is it $\ce{NaBr + H2SO4 -> NaHSO4 + HBr}$ and then $\ce{HBr}$ reacts with $\ce{ROH}$? If yes the why ...
3
votes
1answer
4k views

Decomposition products of PET

On Wikipedia, it says that polyethylene terephthalate (PET) decomposes at temperatures above 350°C. What are these decomposition products? I read further that acetaldehyde is produced, but is that ...
7
votes
1answer
166 views

Ozone catalysis

I know that catalysts don't change chemical equilibrium because they accelerate both the reactions in the same way. I can't understand why CFC catalysts accelerate ozone destruction but not ozone ...
1
vote
1answer
3k views

Why is gold sol used for intra-muscular injection?

In my textbook it is written that gold sol is used for intramuscular injection. But, actually what is its use? Why would people use such a precious element for injection. Can other colloids be used ...
15
votes
5answers
7k views

Can fluorine act as the central atom in interhalogen compounds?

Why can't fluorine be the central atom in inter-halogen compounds? A $\ce{F-F}$ bond is weaker than a $\ce{F-X}$ bond and thus, fluorine should be happy to form inter-halogen compounds. But, why ...
10
votes
3answers
1k views

Why is CCSD(T)/aug-cc-pVTZ not a suitable method for the geometry optimisation of omeprazole?

I know that CCSD(T) with the aug-cc-pVTZ basis set for geometry optimization of omeprazole (5-methoxy-2-[(4-methoxy-3,5-dimethylpyridin-2-yl)methanesulfinyl]-1⁠H-benzimidazole, the active substance in ...
4
votes
1answer
301 views

Intuitive understanding of standard electrode potential

I have read many books on standard electrode potential and they define the term in various ways but I just can’t seem to get an intuitive idea of it. $$\ce{Cu^2+ + 2e- <=> Cu}$$ Standard ...
1
vote
1answer
2k views

SN1 or SN2, the kinetic isotope effect

I know that you can't always trust Wikipedia, so I just want to check something regarding their kinetic isotope effect page. The first example implies that $\sideset{^{12}}\ C$ and $\sideset{^{13}}\ ...
2
votes
1answer
11k views

Why is M1*V1 = M2*V2 only used for diluting solutions?

Why is $M_1V_1 = M_2V_2$ only used for diluting solutions? Why can it not be used to figure out how many moles to add to make a solution more dilute?
2
votes
1answer
4k views

What makes charcoal a good adsorbent to organic and non polar substances while alumina and silica are best for polar substances?

My question is, what makes charcoal a good adsorbent to organic and non polar substances while alumina and silica are best for polar substances?
3
votes
0answers
103 views

What are the key chemical structures of liquid crystals used in display technology?

The majority of current flat screen TVs and computer monitors are based on Liquid Crystal displays. Liquid crystals are compounds that orient under an applied electric field and alter the ...
0
votes
1answer
70 views

What eco-friendly substance can I use to write and erase on a wall for UV glowing without detection in daylight?

I rent an office and want an alternative to a whiteboard and continual dry-erase marker purchases. I can shut out the light and use the surface under UV lamps only, that's fine. Commonly listed ...
7
votes
1answer
805 views

What is the chemical basis for superglues?

There are a variety of different types of glues, some derived from animal or natural materials and some designed by chemists. Some glues need to be activated before they harden and stick (many epoxies,...
3
votes
1answer
761 views

Non-hardening adhesive

I am wondering if any of you know about glue/adhesives that do not harden over time after they are applied or glue/adhesives that take a really long time to harden after application. I need the glue ...
2
votes
2answers
1k views

What type of sensor technologies exist to determine the chemical composition of a polymer?

Let's say I have several pieces of trash and each is made with a different type of material like: Plastic bottle : High Density Polyethylene (HDPE) Cereal box : Paperboard & Epichlorohydrin ...
3
votes
1answer
571 views

Looking for raw interferogram data / raw FID data from FT-IR / FT-NIR / FT-NMR

I'm trying to get my hands on some raw interferogram data / raw FID data from an FT-IR / FT-NIR / FT-NMR so I can run some tests using FFT with it (it needs to be real data). Here's a picture below of ...
11
votes
3answers
243 views

Would it be possible to produce a non-toxic atmosphere using a coal fire and frozen oxygen?

A Pail of Air is a classic science fiction short story by Fritz Leiber from 1951 describing how a family survives on an Earth that has left its orbit around the sun, using desparate low-tech methods: ...
9
votes
1answer
5k views

How can molecularity be the order of the rate determining step?

In my textbook the molecularity is defined as(along with the standard definition) the order of the rate determining step(RDS). It is also given that the order can be a fraction but molecularity is ...
4
votes
2answers
9k views

What is the process of turning ionic silver solution into colloidal silver solution?

I've looked at a number of different colloidal/ionic "silver solution generators." After my research I'm under a few impressions and if they're wrong please let me know. I also am wondering what ...
4
votes
1answer
2k views

How can different no. of unpaired electrons lead to different colours of co-ordination compounds?

To make the question clear I would like to take an example. $\ce{K_3[Fe(CN)6]}$ and $\ce{K3[FeF6]}$ shows different colors in solutions. It is given in my textbook that it is because of different ...
4
votes
2answers
29k views

How to distinguish between benzyl chloride and chloro benzene?

If I add $aq. \ce{KOH}$ to both of the compounds substitution takes place in the case of benzyl chloride and then if I oxidize with $\ce{KMnO4}$ I will get benzene carboxylic acid which will give ...
10
votes
3answers
9k views

Program that simulates basic reactions in organic chemistry

To explain - a friend and I have been working on a program that would allow you to draw organic molecules, indicate the conditions, and predict the products. This would be primarily aimed at basic, ...
3
votes
1answer
211 views

Are there natural conditions that could enable the formation of noble gas compounds?

Noble gases were considered to be inert until compounds that include them, such as xenon trioxide (as an example) were found. My question is, what natural conditions allow the formation of noble gas ...
3
votes
1answer
69 views

Carcinogens, how do they work?

The easiest carcinogenic thing for me to grasp is radiation, as it directly messes with DNA. Then it seems there are other compounds that simply mimic hormones, but these shouldn't necessarily cause ...
12
votes
2answers
9k views

Reaction intermediates of MnO2 catalyzed H2O2 decomposition reaction

Manganese dioxide catalyzes the decomposition of hydrogen peroxide to water and oxygen gas. But what are the intermediates in this catalyzed reaction?
1
vote
1answer
963 views

Solutions, solvents and solutes

In all the chemistry books and eBooks it says that "like dissolves like"... but when it comes to some molecules like ether, cellulose, vitamin A and $\ce{CO_2}$, it confuses me. If we take ether, it ...
0
votes
1answer
286 views

What is the pKa of 2-methyl-2,4-pentanediol?

What is the pKa of 2-methyl-2,4-pentanediol? Is there a reference that contains a list of pKa values for various molecules that I can consult or is there a way to determine/estimate the pKa of this ...
3
votes
2answers
251 views

Is it possible to cut yourself on pyrite?

I am planning an RPG adventure where the characters might end up getting a large cubic lump of "gold", which in reality, as you might have guessed, is in fact pyrite. I also wanted to plan for the ...
1
vote
1answer
21k views

How do I calculate the change in energy of an electron transition?

What are the $\Delta E$'s of the transitions of an electron from $n=5$ to $n=1$ and from $n=5$ to $n=2$ in a Bohr hydrogen atom? The wavelength of the first electron transition is $\lambda_1=409~\...
1
vote
2answers
79 views

Explaining the reaction

i am an immunology master student without prior knowledge of biochemistry. Could someone explain me this 6 reactions ? I could learn the reactions by heart. But i want to understand, why exactly the ...
2
votes
1answer
58 views

Quantum Valence Theory Reference

At least to me, the contents of chapters 5 & 6 given here are representative of discussions on chemical bonding given in nearly all intro general & organic chem books, the statements in those ...
2
votes
1answer
76 views

What is the scaling for % completion time in a Michaelis–Menten scenario as a function of substrate concentration?

Say I have a straightforward Michaelis-Menten reaction where an enzyme $E$ at some fixed concentration $[E]$ forms an interaction complex $ES$ with a substrate $S$ (with initial concentration $[S]_0$),...
0
votes
2answers
5k views

Cheap and not messy solvent for motor oil

I have an old oil cooler of an old Volkswagen engine (the type where the oil itself is cooled, and uses no water) stained with decades of usage. If I pass water through it, it comes out clear, but if ...
12
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5answers
24k views

Why does ZnO turn yellow when it is hot?

Why does ZnO's color become yellow when it is hot? I have read that it is because of physical properties, but I need a more elaborate explanation.
0
votes
1answer
783 views

Units in stoichiometry

$$C_x H_y O_z$$ 1.What are the units of x,y,z.I've read that they're termed as 'stoichiometric coefficients'. 2.What is the unit of mass proportion of carbon(c) in the fuel? $$c=\frac{M_{carbon}}{...
1
vote
2answers
3k views

Balanced reactions at the anode and cathode [closed]

A current of 2.25 A is applied to $\ce{NiCl2}$ solution A. Write the balanced half reaction that takes place at the anode B. Write the balanced half reaction that takes place at the cathode Can ...
11
votes
1answer
923 views

What molecular features create the sensation of sweetness?

There are many compounds that taste sweet. Many of the artificial ones taste much sweeter than natural sugars (which is why they contribute little to energy intake when use as sweeteners). A range ...
7
votes
1answer
30k views

How do you determine a chemical formula given the molecule's crystal structure?

How do you determine the chemical formula of a compound given its crystal structure?
4
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1answer
979 views

Silver-promoted reaction of alkyl halide with diphenyl sulfide

What is the major product formed when 1-chloro-3-iodopropane reacts with diphenyl sulfide in the presence of one equivalent of $\ce{AgBF4}$? I know that sulfur is nucleophilic and that it can ...
0
votes
3answers
8k views

Metallic properties of iodine [closed]

Why does iodine exhibit metallic properties at room temperature although being a non-metal? Are there any similar elements like this?
2
votes
1answer
1k views

Thermodynamics and equilibrium constant [duplicate]

I just wanted to make sure how we can know whether it is $K_c$ (equilibrium constant of concentrations) or $K_p$ (equilibrium constant of pressures) which "comes out" of the equation, $\Delta G^o= -RT ...
2
votes
1answer
1k views

Thermodynamics effect of change of temperature on equilibrium

I'm studying thermodynamics and I don't understand, why, when we are asked which effect has a rise in temperature on the equilibrium constant of a reaction, we can't use the formula: $\Delta G= \Delta ...

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