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4
votes
0answers
55 views

How to compare the bond angle of ozone and nitrite anion [closed]

How do I compare the bond angle between $\ce{O_3}$ and $\ce{NO_2^-}$ ? I've studied how to compare the bond angle when normal covalent bonds are present where the electrons are shared in the bond and ...
5
votes
4answers
212 views

What's the purpose of significant figures in measurements?

I have read about this topic in both of my chemistry and physics books, but none of them exactly pointed out the significance of the significant figures. Then I searched the Internet for the same and ...
2
votes
1answer
43 views

How to determine the equivalents of OH- in a titration curve

How does one go about determining the equivalents of $\ce{OH-}$ needed for the titration of a weak acid. For example here is the titration curve for Aspartate: Why is the equivalents for $\mathrm{p}...
0
votes
2answers
36 views

Finding freezing temperature and osmotic pressure of an ethylene glycol and glycerol solution in water

A water solution is prepared by mixing $\pu{200 g}$ of a ethylene glycol (ethan-1,2-diol; $\ce{C2H6O2}$) solution (20% by weight) with $\pu{500 g}$ of glycerol (propan-1,2,3-triol; $\ce{C3H8O3}$) ...
-4
votes
0answers
29 views

Does nitrogen oxide react violently with water? [duplicate]

We are going to clean an ozone generator. I understand the residue will be nitrogen oxide. When we rinse, is the mixing of water with the nitrogen oxide an exothermic or violent reaction?
4
votes
2answers
270 views

What is the major product in the reaction between 4-chloropentanal and lithium aluminium hydride?

What would be the major product between 4-chloropentanal and $\ce{LiAlH4}$? After the reduction of the aldehyde, would the hydroxyl group formed at $\ce{C-1}$ attack $\ce{C-4}$ causing cyclization to ...
6
votes
1answer
147 views

Why is it advised to use neutral ferric chloride solution while performing confirmatory test for acetate ions? [duplicate]

The reaction of $\ce{FeCl3}$ with $\ce{CH3COO-}$ is $$\ce{3Fe^{+3} +6CH3COO- +H2O<=> [Fe3(OH)2(CH3COO)6]^{+} +2H^{+}}$$ Recently I read that a solution of $\ce{FeCl3}$ hydrolyses very quickly to ...
0
votes
0answers
29 views

Are ekaconjugated polymers used as dielectrics? If not, why so?

So I came across an article called "Giant polarization in high polymers" and I was wondering if there was a reason why these types of polymers haven't found use in capacitors at this point. ...
6
votes
1answer
66 views
+100

Is Thermoplastic Rubber Food/Pet Safe? Confusions between TPR and TPE

I'm not sure if this is the correct place to post this or if I should be posting at Crafts or Engineering, but since my primary concern is about the safety of its use for my dogs I will post here. I ...
2
votes
0answers
39 views

Significance of the ground state energy in quantum chemistry?

In quantum mechanics, quantum chemistry, and condensed matter physics courses, it seems like finding the ground state energy of a Hamiltonian is incredibly important. I can understand why having the ...
1
vote
2answers
70 views

To which extent is protein folding conserving subprotein structures?

I am actually a pure mathematician, who stumbled over this paper «Protein-Folding Analysis Using Features Obtained by Persistent Homology» by Ichinomiya et al. (Biophys. J. 118, 2020, 2926-2937; link),...
-5
votes
2answers
86 views

What would happen if the alpha particles directly hit the electrons in the gold foil in Rutherford's experiment? [closed]

What would happen if the alpha particles directly hit the electrons in the gold foil in Rutherford's experiment? Would it get ionized or is there no probability of such a thing happening ?
0
votes
0answers
29 views

Relation between Ionization energy and reactivity

So I was learning about the periodic table where I came across the topic of ionization energy. As a general trend the Ionization energy decreases as we move down a group with a few exceptions such as ...
3
votes
0answers
42 views

Why does an improper rotation axis preclude chirality?

Can anybody prove that any molecule with an axis of improper rotation is nonchiral? I still do not understand why this is so, any proper mathematical proof or visualisation of a generalised molecule ...
0
votes
0answers
24 views

First ionization energy and electron gain enthalpy of dihydrogen / stability comparison of dihydrogen ions [duplicate]

Subset of: How can antibonding orbitals be more antibonding than bonding orbitals are bonding? Stability of $\ce{H2^{-}}<\ce{H2^{+}}<\ce{H2}$ Stability of $\ce{N2^{-}}<\ce{N2^{+}}<\ce{N2}...
11
votes
1answer
452 views

Does folic acid contain a benzyl or a phenyl group?

I'm studying for my MCAT currently and I stumbled upon this question. It gives the structure of a folic acid molecule and asks what functional groups can be found within the molecule. I understand ...
1
vote
1answer
64 views

Do superoxide salts of heavier alkali metals contradict the principle that lattice energy depends inversely on cation-anion distance?

I have a very basic understanding of quantitative lattice energy calculations: I only know that the lattice energy is directly proportional to the product of charges on the ions and inversely ...
-1
votes
0answers
20 views

Electron configuration of the Superactinoids (Z > 118) [duplicate]

I have a question: Do I see it correctly that the electron configuration of the superactinoids given in wikipedia was somehow calculated differently (quantum mechanically?); e.g. Z=119: [Og] 8s1 Z=...
2
votes
1answer
51 views

Is it possible to filter Stille catalysts using syringe filter?

I'm conducting an organic synthesis involving Stille coupling. Stille coupling uses $\ce{Pd2(dba)3}$ and $\ce{P(o-tol)3}$ as catalysts. Both catalysts dissolves in toluene which is the solvent of my ...
1
vote
1answer
57 views

What is the solubility trend of alkaline earth metal fluorides?

I was going through JD Lee and I found certain contradictory statements. First: With most compounds, on descending the group, the hydration energy decreases more rapidly than the lattice energy: ...
2
votes
1answer
38 views

How do I label stereogenic centers R or S when there are 3 bonds in the plane and 1 bond coming out?

I need help with question (d). I labeled the O the first priority, then the C that's bonded to an O the 2nd, and the C above that is attached to 3 other C's the 3rd priority. So, I ended up getting S, ...
0
votes
1answer
21 views

d orbital irreducible representations in metal in ML4 model [closed]

In ML4 (Metal—4 ligands)model which has a square planar shape and D4h point group, what is the irreducible representation for the 5 kinds of d orbitals in the central metal?
2
votes
1answer
49 views

The dependency on electron density in the reactivity order of electrophilic and nucleophilic additions

It is well-known that for electrophilic addition across an alkene, the reactivity increases when intermediate carbocation is more stable (eg. addition of $\ce{HBr}$ or acid-catalyzed addition of $\ce{...
2
votes
1answer
51 views

Can the paper in thin layer chromatography be any type of paper?

I'm doing a chemistry chromatography lab that wants me to recreate anything I want. I decided to measure how far a pigment goes in each color for the same brand, but I'm stuck at the paper part. I ...
3
votes
0answers
49 views

Why is NaCl so abundant in the ocean [closed]

Why is sodium chloride far and away the most abundant salt dissolved in ocean water. Its two constituent ions do have a very high frequency in the crust of the earth but they are far from the most ...
3
votes
0answers
38 views

Labelling of molecular motor isomeric forms as trans and cis

I am reading Koumura et al. (2002), a paper about molecular motors. It contains this figure: Being an absolute layman when it comes to naming my molecules I'm a little confused as to why the left ...
2
votes
0answers
28 views

How to selectively adsorb caffeine on activated carbon filter?

As part of a project on decaffeination methods, I'm looking to see how activated carbon filters can selectively adsorb caffeine in tea and coffee solutions, and avoid adsorbing other taste-giving ...
2
votes
0answers
46 views

What causes horizontal lines on an excitation-emission matrix in fluorometry?

I am doing excitation-emission matrices to test for CDOM, and we just got some brand new quarts cuvettes. When I hold them in front of a light, they're totally clear and clean. I ran a sample, and in ...
1
vote
0answers
41 views

Limitations of Quantum Chemistry [closed]

I have a physics background and I am interested in the applications of quantum mechanics in predicting chemical reactions, and I’m wondering where should I start? I am particularly interested in the ...
1
vote
0answers
27 views

Which temperature would allow a molecule to vaporize at ultra-low pressure? [closed]

I must vaporize a molecule with a normal boiling point of 320°C. Now I work with ultra-high vacuum and I need to bring my molecule to the gas phase. Has anyone a rough idea how high the temperature ...
3
votes
0answers
62 views

Does vinyl chloride deactivate the benzene ring?

I came across the following option of a multiple choice question (The options are in the form of assertion and reasoning side-by-side and the incorrectly matched statements are to be marked): ...
2
votes
1answer
255 views

Why is the bond angle of trifluoromethane higher than that of difluoromethane?

The bond angle $\ce{\angle(F-C-F)}$ of $\ce{CHF_3 > CH_2F_2}$ whereas that of $\ce{\angle(Cl-C-Cl)}$ is $\ce{CH_2Cl_2 > CHCl_3}$ why is this the case? Some explanations I read suggest the Bent's ...
0
votes
1answer
28 views

Is equilibrium point for a coupled equilibria of arbitary number of coupled reactions is a unique point?

I was solving a question of salt hydrolysis for a mixture of Weak Acid-Base Salts, given the initial amount of salt and Equilibrium constants. I was trying to approach the problem in two ways, ...
2
votes
1answer
29 views

Is diethyl and methyl preferred over an ethyl and an isopropyl group as substituents when both give the same longest chain? [duplicate]

According to what I took (look for the longest chain, start close to the branches, etc etc) I see two paths I could follow to give me a hexane. One where you go through the carbon in the methyl, and ...
1
vote
2answers
57 views

Combustion and oxidation [closed]

What is the difference between combusting and oxidizing? Oxidation of alcohols leads to formation of aldehydes and carboxylic acid whereas the combustion of alcohols leads to the formation of carbon ...
-5
votes
1answer
28 views

buffer “recipe” needed [closed]

I have a question, that I hope can be answered without the respondant showing off how much they know about chemistry and talking in "words of art". It's been 50 years since I tool chemistry ...
0
votes
1answer
69 views

What is the radial probability distribution function and what is its significance? [duplicate]

Below I have given three graphs for the $\ce{1s}$ orbital. $R(r)$ is the radial part of the wave function of the electron. $R^2(r)$ is the radial part of the wave function of the electron multiplied ...
2
votes
0answers
37 views

Entropy change during electrolysis of water

Consider the electrolysis of water reaction: $$\ce{H_2O -> H_2 + 1/2O_2}$$ At room temperature and atmospheric pressure, the change in enthalpy of this reaction is $\Delta H = \pu{+286 kJ mol-1}$. ...
3
votes
0answers
61 views

Is sulphonamide group prone to undergo diazotization?

I wonder if it is not a problem that there is another $\ce{-NH2}$ group in the molecule not connected to aromatic ring and if it can get protonated and react with $\ce{HNO2}$ too, in this case the one ...
-4
votes
0answers
38 views

why Ni(CO)4 , being tetrahedral, is yet a low spin complex

I have read that tetrahedral complexes are rarely low spin and mostly form high spin complex irrespective of ligand strength because pairing energy is greater for tetrahedral complexes. I wanted to ...
2
votes
0answers
37 views

In the mechanism of Cannizzaro reaction, how do we rationalize hydrogen acting as leaving group? [duplicate]

Mechanism of Cannizzaro from wikipedia I am trying to understand how to rationalize in the first step of third row that the hydrogen act as a leaving group and a nucleophile. After googling, I found ...
1
vote
0answers
22 views

Hydrogen permeation from low to high absolute pressure area due to difference in partial pressure?

I need to get help with a question regarding hydrogen permeation which I do not really how to get around. The statement is as following: A steel container contains helium gas at high pressure (100 ...
1
vote
1answer
76 views

Why is it technically inaccurate to say that the decrease in reactivity of halogens is due to decreasing electronegativity?

I came across the following information in this post. Below the infographic there is a paragraph with a disclaimer: As another disclaimer, the reactivity of the halogens decreasing down the group ...
1
vote
0answers
99 views

Using bis- over di- as multiplicative prefix in the nomenclature of urea for coordination complexes [duplicate]

The compound $\ce{[CuCl2(NH2CONH2)2]}$ is named as dichloridobis(urea)copper(II). However, why is it not dichloridodiureacopper(II)? I know that we use bis-, tris-, tetrakis- when the ligand's name ...
-1
votes
0answers
20 views

Origin of london dispersion forces [duplicate]

I have learnt that the electrons tend to stay the farthest apart from each other in the atomic orbitals. If so, then when they revolve around the nucleus, they should have stayed farther apart from ...
1
vote
1answer
55 views

Hydrogen Peroxide & Vinegar Film reversal, can someone help me understand this reaction?

I'm interested in DIY photo development and I came across a reversal process that uses chemicals easily available at the grocery store. The purpose of a reversal process is to take a partially ...
2
votes
1answer
17 views

Find atomic radius from angle, wavelength, (311) plane and FCC structure

I've worked this problem and seem to be off by a factor of $2$ somehow. From Callister, 6th edition, problem 3.56W (but I don't have access to the "W" web material that actually explains ...
0
votes
0answers
29 views

How to know if an isotope is stable for balancing nuclear reactions?

Write the balanced equation for the reaction of $\ce{^14N}$ with an $\alpha$ particle. JEE adv-1997 From the basics I knew of alpha particle, I just added the atomic mass and proton numbers: $$ \ce{^...
1
vote
1answer
24 views

diprotonated vs monoprotonated inorganic phosphate

We have made confounding observations in the physiology lab working with inorganic phosphate. The cell processes we study rely upon the transport of diprotonated inorganic phosphate. But we get ...
5
votes
0answers
25 views

Do the differential expressions of second law of thermodynamics imply a smooth increase in entropy? [closed]

Another statement of second law of thermodynamics can be formulated in terms of system properties and not properties + surroundings (isolated system). For a closed system at constant temperature and ...

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