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votes
0answers
35 views

Ionic vs covalent behavior of sodium [closed]

The given chemical reaction: $$\ce{R-OH + NaBr + H_2 SO_4 \bond{->} R-Br + NaHSO_4 + H_2O}$$ I wanted to write the chemical mechanism of the chemical reaction, given above, but I'm facing a bit ...
-3
votes
1answer
49 views

Does LPG (cooking gas) react with water? [closed]

If cooking gas (or LPG) was exposed to some water in the gasline system, what would be the resultant by-product, and would this induce flame into the cylinder for explosion?
-3
votes
1answer
36 views

Comparison of stability of aromatic compounds [closed]

What is the basis of comparison between two aromatic compounds having different ring structures Like in propyl and heptyl rings
3
votes
4answers
126 views

Heisenberg's uncertainity principle(HUC)

I know the mathematical form of HUC and its statement i.e.It is impossible to determine simultaneously. , the exact position and momentum of an electron. i don't know why this ...
0
votes
1answer
48 views

One mole of solute (NaCl) is dissolved in 1 litre water. The molarity of solution is [closed]

One mole of solute ($\ce{NaCl}$) is dissolved in $\pu{1 L}$ of water. The molarity of the solution is: A) $\pu{<1M}$ B) $\pu{>1M}$ C) $\pu{=1M}$ D) $\pu{=2M}$ My answer: It’...
2
votes
1answer
39 views

Conditions for molecular dissymmetry

In my textbook, under the topic "Asymmetric and Dissymmetric Compounds", the following statement is given: A molecule which does not possess plane of symmetry, centre of symmetry, and alternating ...
0
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0answers
10 views

What is difference between molecular mechanics and molecular dynamics study? [on hold]

Can anybody tell the difference between molecular mechanics and molecular dynamics study with example.
1
vote
1answer
37 views

Doubt in conditions for geometrical isomerism

In my textbook, under the topic "Conditions for geometrical isomerism", the following has been given: Groups responsible to show geometrical isomerism must be nearly in the same plane. Is this ...
0
votes
0answers
27 views

How do you find the heat capacity ratio of combustion products?

For example, if gaseous oxygen $(O_2)$ and paraffin wax $(C_{32}H_{66})$ were to stoichiometrically combust at STP, how would one go about finding the heat capacity ratio ($\gamma={c_p \over c_v}$) of ...
0
votes
0answers
32 views

Finding Bond moment of O-H bonds of water

While finding bond moment of water we take the dipole moment of water as the vector sum of two O-H bonds and we calculate it to be 1.51D. But the lone pair is also present which affects the dipole ...
-2
votes
1answer
23 views

pressure equalization [closed]

Suppose we have a closed container A containing certain gas at normal room temperature. Now this container is connected to another similar closed container B having same volume through a narrow tube, ...
-1
votes
1answer
44 views

Cup with vinegar/salt/copper solution previously in it ran through dishwasher

Someone enjoys making jewelry, and saw an online tutorial saying that you can mix equal parts of vinegar and salt, and leave copper in it for a while to oxidize it, and turn it green. After doing ...
0
votes
1answer
33 views

How to pool fractions after chromatography?

I used chromatography to purify my protein and now I have fractions with different concentrations ranging from 1-16 mg/ml. Should I pool all these fractions or just the ones with high concentration (...
0
votes
2answers
57 views

Coffee cup lids

So this morning I purchased a coffee. As a not uncommon event the lid on the coffee cup didn't have a hole completely punched through (a gas inflow hole). This makes it difficult to drink the coffee ...
0
votes
0answers
37 views

How does sticker residue interact with sunscreen? [closed]

I've tried it myself and it works like a miracle. That nasty residue that sticks to the bottom of plates, glasses, etc, you just spread some sunscreen onto it, wait a couple of minutes and then rub it ...
3
votes
1answer
61 views

Lactone acylation

Can anyone propose/draw a mechanism for Method A, below, from this paper? Almost all other literature use method B and reagents such as SOCl2.
-1
votes
1answer
28 views

Emulsifier for water, been oil [closed]

I am trying to blend neem oil and water and I'm wondering what the best emulsifier would be 10% neem oil 90% water thank you
0
votes
1answer
48 views

Volume of a gas

The kinetic theory assumes that, for an ideal gas, the volume taken up by the molecules themselves is entirely negligible compared with the volume of the container. For a real gas, that assumption isn'...
-1
votes
0answers
29 views

Why doesn't HCl have hybrization, even when it has polar covalent bond?

I read that HCl has a polar covalent bond and I also read that atomic orbitals undergo hybridization to form hybrid orbitals and form covalent bonds. But according to a few answers on Quora, it is ...
0
votes
0answers
15 views

n+l rule for first member of lanthanide and actinide series

as we all know that if the value of $n+l$ is same then the orbital with lower value of $n$ will get filled first so in case of first member of lanthanide series the configuration is $(\ce{Xe})\mathrm{...
0
votes
2answers
89 views

What is the origin of the Quadratic factor in calculation of XRD peaks?

Whenever we are to calculate the d-spacing(for cubic system) in XRD peaks with reference to Quadratic Factors we do that with the help of the formula $$\frac{1}{d_{hkl}^2}=\frac{h^2+k^2+l^2}{a^2}.$$ ...
0
votes
1answer
33 views

Confused with 'discharge potential',preferential discharge theory

My book says that the ions which have least value of discharge potential are deposited first in the concerned electrode because the 'require' the least energy to do so.I am confused by 'require' , do ...
0
votes
0answers
32 views

How to calculate the lifetime of a triplet excited state? [closed]

I have this molecule, crotonic acid, the question is that is there any approach that I can calculate or estimate the lifetime of the triplet excited state of crotonic acid, assuming all the needed ...
1
vote
0answers
30 views

How did Thomson calculate the momentum of electron when he didn't know the mass of electron?

"This was proven in 1903 by J. J. Thomson who calculated that the momentum of the electrons hitting the paddle wheel would only be sufficient to turn the wheel one revolution per minute." This is a ...
0
votes
1answer
39 views

Does 1,3-butadiene in bromine/water do addition twice?

Considering 1,3-butadiene (below) added to bromine water (considering it as $\ce{Br2(aq)}$): I've seen online that the products are 1,2-dibromobutene and 1,4 but what I don't understand is why ...
9
votes
1answer
492 views

The heat content of the products is more than that of the reactant in an … reaction

The heat content of the products is more than that of the reactant in an ............. reaction. In this question the answer given is "exothermic"; yet I thought the answer would be endothermic as ...
2
votes
1answer
40 views

Finding structural isomers of an alkene

I am doing problems on finding structural isomers. I am asked to find the structural isomers of $\ce{C5H10}$. The answer to problem states there are 10 structural isomers possible. I was able to find ...
1
vote
1answer
49 views

How to determine pressure and concentration of carbon dioxide in blood plasma?

A man suffering from untreated diabetes mellitus is admitted to a hospital. Doctors fear that his blood $\mathrm{pH}$ may have dropped because of ketoacidosis. Analysis of his blood reveals that $[\ce{...
0
votes
0answers
16 views

Formal charge: size vs electronegativity?

My question is why size is not taken into consideration when deciding major contributors of resonance structures, particularly: why is the formal charge always assigned to the most electronegative ...
-1
votes
1answer
34 views

How can I prepare two phosphate buffer of different concentrations but give same pH? [closed]

How is it that buffers of different compositions can have the same pH? For example, it is possible to prepare 0.01 M phosphate buffer of pH 7.0 and 0.1 M phosphate buffer of pH 7.0? How? I used ...
2
votes
1answer
72 views

Could Calcium Oxide be made from CaCO3 in a bonfire?

I have some chalk and I need to turn it into CaO. Would a big bonfire be hot enough to make it? If anyone has personal experience with this reaction please share, whether succesful or not
1
vote
2answers
49 views

Energetic stability in relation to α-hydrogens

I am new to organic chemistry and was asked to rank the following materials according to energetic stability. I think I have understood that the way to do this is to count the amount of α-hydrogens: ...
0
votes
0answers
11 views

How can I explain PEO-b-PLA behaviors in dissolution?

I dissolved PEO 10K - PLLA 14K in toluene at the concentration of $\pu{50 mg/ml}$, $\pu{25 mg/ml}$, and $\pu{5 mg/ml}$ including $\pu{30 min}$ of sonication. When I sonicated them at room temperature,...
-1
votes
1answer
38 views

How to find the resist in pH change when both are same buffers of same concentration? [closed]

We are given two buffers [a) 0.1 M phosphate buffer of pH 7.7 and (b) 0.1 M phosphate buffer at pH 6.71 . If acid is to be added to the buffers, which of them, will resist the pH changes better I ...
1
vote
0answers
40 views

What does a simple or a complex substituent mean? [duplicate]

I am reading rules for IUPAC Nomenclature. The following statement is from my book. Prefixes di, tri, tetra, etc., are not considered in deciding alphabetical order for simple substituents but ...
1
vote
0answers
27 views

Predicting atomic weight and density of calcium [closed]

I have a question from school: Assuming that the element Ca had not been discovered, predict using the properties of the known element surrounding Ca its own properties such as its atomic weight ...
3
votes
0answers
46 views

Parameters by which to distinguish SN1 from E1

I am new to organic chemistry and am struggling with the following very basic question: Given is the following reaction: $$\ce{(CH3)3CCl + NH3(aq) →}$$ I am supposed to analyse the end-product (the ...
0
votes
1answer
49 views

Does it sometimes take energy to create a chemical bond? [duplicate]

Wikipedia says so: Bonds can also be broken apart. Since most bonds require energy to form, they also give off energy when they are broken. But before most bonds break, the molecule has to be ...
7
votes
1answer
134 views

Gold Plating on Glass?

I am considering labware options to handle NaOH solutions at ~150°C. One appealing idea would be to coat my current glassware with gold. I've read different sources mentioning the possibility without ...
0
votes
0answers
10 views

Explanation of SN2 Mechanism using MOT

SN2 is usually explained by MOT, where we state that the incoming nucleophile starts donating the electron density into the σ∗ orbital and the carbon-leaving group bond weakens and finally breaks and ...
0
votes
0answers
19 views

Can a molecule having only centre of symmetry be called meso? [on hold]

Correct me if I am wrong , meso compunds are optically inactive due to internal compensation.
2
votes
0answers
27 views

NaOH vs Polypropylene

This source lists polypropylene as suitable for use with NaOH. However, this paper seems to demonstrate that NaOH slowly degrades polypropylene (even at fairly moderate temperatures). Does anyone ...
0
votes
1answer
33 views

will charcoal briquettes (not activated) absorb water out of the air in the house in a sub tropical climat?

I live in Florida--incredibly wet environment-very difficult to get moisture out of house w/o using de-humidifier 24/7--which is too expensive. Would charcoal briquettes be of any use?
4
votes
0answers
53 views

Are primitive GTOs normalised before contraction, or is the resultant basis function normalised afterwards?

I'm quite curious about this: In a basis set (I'll just use minimal-basis STO-nG basis sets for convenience), the basis functions are written as a linear combination of primitive GTOs. Are the GTOs ...
0
votes
0answers
46 views

Why are $\ce{SO3}$ and $\ce{NO3-}$ not isoelectronic, even though $\ce{SO3}$ has the same number of outer electrons as $\ce{NO3-}$

Though $\ce{SO3}$ has the same number of outer electrons as $\ce{NO3-}$, the two are not isoelectronic This statement is from JD Lee but I could not understand why is he calling these two molecules ...
1
vote
0answers
16 views

Why do the d orbitals contract when pairing of electrons start, because the size should increase due to increase in energy

The energy of an orbital is proportional to its mean radial distance, and since the 3d orbital is much larger it is much higher in energy than the 3s and 3p orbitals All references from JD Lee ...
2
votes
1answer
71 views

Probability density “AT” the nucleus?

Just had a conceptual question from radial wave functions. I wanted to know if probability density AT the nucleus is maximum, or zero. From the attached images, it is clear that the function is at ...
3
votes
0answers
25 views

Are Slater’s rule and lanthanide contraction contradictory?

According to most textbook and the Wikipedia page of lanthanide contraction, the phenomenon is due to poor shielding of nuclear charge by 4f electrons. However, the σ value of 4f electrons to 6s is 1....
-7
votes
1answer
41 views

What Is the Difference Between Radiation and Radioactivity? [closed]

Does all radiation glow green and mutates people on contact?
0
votes
0answers
25 views

How to find out the value of 'n' in the equation (ΔG = −nFE)? [duplicate]

I can figure out the value of 'n' in simple equations like Fe³⁺ + e⁻ → Fe²⁺ (which would be n=1 here.) But in equations like 2Cu⁺→ Cu²⁺ + Cu, I can't figure it out. I assumed the value of n would be ...

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