# All Questions

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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 ...
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?
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
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### 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 ...
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### 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’...
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### 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 ...
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.
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 ...
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 ...
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 ...
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, ...
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 ...
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 (...
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 ...
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 ...
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### 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.
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
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### 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'...
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 ...
15 views

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### 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 ...
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 ...
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
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: ...
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,...
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 ...
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 ...
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 ...
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 ...
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### 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 ...
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 ...
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 ...
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.
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 ...
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### 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?
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### 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 ...
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### 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 ...
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### 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 ...
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### 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 ...
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....