6
There is no evidence (e.g. aromaticity) to support your claim that the compound is planar. In fact, crystalographic studies [1] revealed existence of both cis- and trans-3,6-dimethylpiperazine-2,5-dione. Corresponding CCDC numbers are LCDMPP01 and TRDMPP01, respectively — feel free to open the links and play around with the 3D structures in JSmol to ...
5
The method presented by Yusuf is a simplified model, which works best for well-behaved molecules. Unfortunately in this case it presents the 'correct' result based on incorrect assumptions. (Even though I did a calculation, I am not 100% convinced this is actually the correct result in the first place.)
In order for the resonance to stabilise a negative ...
3
The ideal formulation of rocket fuel is a balanced mix of oxidizer and fuel. A strong oxidizer and a highly flammable compound or strong reducer, which is termed the "fuel", Is the Ideal combination for a fuel that will combust hypergolically when mixed. The compounds in hypergolic fuels are ideally liquids, because fluidity allows for easier mixing.
As ...
3
Naturally occuring amino acid with basic sidechain - L-Arginine:
Oral supplementation with L-arginine at doses up to 15 grams daily are generally well tolerated.
source here
3
You can take both factors (1) and (2) combined as the reasoning for the greater acidity of the former.
When you are comparing stability (in thermodynamic terms) of two conjugate bases, you are basically trying to position them with respect to each other on the energy axis of the energy profile (or reaction coordinate diagram).
In this case, the reaction ...
3
The vicinal-glycols can be cleaved to corresponding aldehydes and/or ketones in high yield by the action of periodic acid ($\ce{HIO4}$) or lead tetraacetate ($\ce{Pb(OAc)4}$). This oxidative cleavage of a carbon-carbon single bond provides a two-step involving cyclic intermediate reaction mechanism with high-yield. A generally accepted equation for these ...
3
Although I am conversant with this aspect of thermochemistry, it is not my area of expertise. Nonetheless, your question as to why branching leads to a lower heat of combustion in a set of alkane constitutional isomers is one that has intrigued me for sometime. So much so that, after asking former peers steeped in physical organic chemistry, they were at a ...
3
Branched-chain alkanes have lower values of ΔcH⊖ than straight-chain alkanes of the same number of carbon atoms, and so can be seen to be somewhat more stable. https://en.wikipedia.org/wiki/Alkane#Branched_alkanes
The heats of formation are given in https://en.wikipedia.org/wiki/Standard_enthalpy_of_formation and go from -40.0 kcal/mol for a to -41.8 for b ...
2
Let's look at following table from a Yale website:
$$
\begin{array}{c|ccc}
& \ce{(CH2)3} & \ce{(CH2)4} & \ce{(CH2)5} & \ce{(CH2)6} & \ce{(CH2)7} \\
\hline
\Delta H_\mathrm{Combusion} \ (\pu{kcal/mol}) & -499.8 & -656 & -793.5 & -944.6 & -1108.3 \\
\Delta H_\mathrm{Combusion} \text{ per } \ce{-CH2}- \ (\pu{kcal/mol})...
2
The Lemieux-Johnson oxidation (details here) using catalytic $\ce{OsO4}$ or $\ce{RuO4}$ turned over with $\ce{NaIO4}$ will do the transformation you want in one step. These conditions should be selective for the exo double bond.
2
Because your hands are covered in a thick crust of dirt, dust and fats, in which the virus can hide.
But anyway still nobody has been able to show that this virus is regularily (or even rarely) transmitted via smear infection. (If someone knows about any evidence to the contrary, please come forward. And yes, some other diseases, especially bacterial ...
2
When two or more double bond are present then the more electron rich double bond will epoxidise. In above example the double bond containing the methyl group has electron donating inductive effect while the double bond containing the methoxy group will have an electron donating resonance effect. The resonance effect is dominant over the inductive effect....
1
You may wish to give this suggestion a try, courtesy of the literature on constructing nano-particles.
First, dissolve the protein samples in say ethanol or other flammable solvents.
Next, place it into an alcohol lamp with a wick composed preferably from glass fiber, but one may be able to employ woven cotton or a cotton string.
Lastly, light the lamp ...
1
HCL is a stronger acid so it will displace the bitartarate forming choline hydrochloride and tartaric acid
1
So, there are many factors that affect acidity or basicity of a compound, the main factors being bond electronegativities and resonance structures. However, I believe you are correct in assuming that those pKa values seem a bit off. Upon further investigation, I found that 10.8 is the pKa of the conjugate acid of ethanamine, so the pKa of the actual compound ...
1
The problems with reacting pure nylon salt are as follows:
The molecules of hexamethylene diamine (HMD) and adipic acid will have a very hard time accessing each other's reacting groups, because of limited mobility within the solid structures.
The reaction is a condensation, so it will produce a substantial amount of water anyway, so pretty much any reason ...
1
Why benzene takes in more delocalized electrons from its substituents even though it has six of them
Using atomic orbitals to construct molecular orbitals involves some shifting and redrawing because of overlaps. Benzene is symmetrical, so whether you draw six carbon atomic p-orbitals or squash and spread them out, you get the idea. Now, when you look at phenol, the C-O bond is unsymmetrical, so if you want to be more precise, you say that oxygen draws some ...
1
There is a significant quantum probability a delocalized electron is there, what in average attracts atoms together, compared to the state there was no such an electron.
E.g. for benzene, the distance is shorter than for a single bond, but longer than for a double bond, being effectively 1.5 bond.
1
One path to safely determine the strength of H2O2 is:
First dilute it to 1/3 strength (this is for safety when dealing with higher concentrations of hydrogen peroxide).
Slowly titrate against a known concentration of NaOCl until the vigorous oxygen liberation ceases.
One can also collect the volume of O2 evolved.
Reaction equation:
$\ce{NaOCl + H2O2 -> ...
1
Okay, so if we talk about the acidic strength of a compound, consider adding a base to a solution of all the above. Practically, a reaction is bound to take place-if possible-due to thermodynamic reasons. Hence, reaction in IV will take place since the base will try to find the most acidic Hydrogen, which is why one should consider the removal of H atom from ...
1
One example of a reaction like this is the reaction of Benzaldehyde and Formaldehyde in the presence of a basic hydroxide (OH-).
This reaction proceeds as follows:
Thus, using Sodium Hydroxide (NaOH), The reaction would yield Phenylmethanol (C6H5CH2OH) and Sodium Formate (HCOONa, sodium salt of formic acid)
If you want a better answer, or if this was not ...
1
It is well known fact that branched-chain alkanes are more stable than the straight-chain alkanes with the same number of carbon atoms. That means branched-chain alkanes have higher values of enthalphy of formation ($\Delta H_f^\circ$) than that of straight-chain alkanes with the same number of carbon atoms.
During the complete combustion reaction with ...
1
Here is a short simple available answer provided online by Prachi Sawant in 2016 to quote:
Formic acid has both aldehydic (-CHO) and carboxylic (-COOH) functional groups.
Hence, it gives both Tollen's and Fehling's test positive.
Reaction of formic acid with Tollen's reagent:
$\ce{HCOOH + 2[Ag(NH3)2]+ +2OH- → 2Ag + CO2 + 2H2O + 4NH3 }$
...
Only top voted, non community-wiki answers of a minimum length are eligible
