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22 views

Hybridization of terminal O atoms in ozone [duplicate]

Most searches about the question of hybridization of O atoms in ozone only deal with the middle O atom, which is sp2. The outer ones are either sp2 or sp3 hybridized depending on which individual ...
1
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1answer
33 views

Nano coatings reaction with Al bottles

I have a question regarding nano coatings based on the formula "modified $\ce{SiO2}$". I have been told that $\ce{Al}$ bottles react with substances with a $\mathrm{pH}$ value below 3 or above 9. ...
1
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1answer
50 views

What is the “mechanism” of the decomposition of hydrogen peroxide?

In my classwork on the decomposition reaction of hydrogen peroxide by catalase, I wrote the following equation: $$\ce{2H2O2 -> 2H2O + O2}$$ However, my teacher said that I should go further in ...
-1
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1answer
48 views

Do ions in a salt bridge come from the half cells in electrochemistry?

I understand the basics of electrochemsitry and galvanic cell, where there are half cells where either an oxidation or reduction reaction occur, and electrons moving between the wires provide the ...
2
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0answers
30 views

DIY chemistry - Calcium from bone [closed]

I've gotten really into this subject lately from people who make their own cleaning agents and I was surprised how simplistic (although time consuming) everything was. I am interested in making ...
4
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0answers
33 views

Are there any theorems about packing of atoms in molecules subject to the Lennard-Jones potential?

Related to the problem of minimization of the Lennard-Jones potential in a molecule with $n$ atoms, where $n$ is, say, between $5$ and $10$, questions arise such as (but not limited to) the following: ...
-1
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1answer
45 views

Why fibres are strong only in one direction? [closed]

Why fibres are strong only in the direction they are oriented?Why they break if we pull at right angle to their orientation? Here each blue line represents combination of polymeric chains.
4
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0answers
36 views

membrane for a reverse osmosis desalination experiment

We are second year cram schoolers , we are currently working on a project tackling water desalination by reverse osmosis and are required to do an experience. During the process, we encountered some ...
0
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0answers
21 views

Are Hansen solubility parameters available for technical metals and alloys?

Are Hansen solubility parameters available for technical metals and alloys (e.g. aluminium, cast iron, different steels)? Hansen solubility parameters are available not only for solvents and polymers ...
3
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1answer
73 views

Estimation of ground state energy from wave function [closed]

Given the wave functions of a particle in a 1D box below determine (for each pair) if the left or right function gives a better estimation of the ground state energy if the variational method is used. ...
0
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0answers
24 views

Are Hansen solubility parameters available for inorganic salts or ionic molecules?

Are Hansen solubility parameters available for inorganic salts or ionic molecules (e.g. potassium oleate, potassium stearate, sodium dioctyl sulfosuccinate (AOT), sodium dodecyl benzol sulfonate (SDBS)...
2
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1answer
62 views

Reaction of octahydroazecine with iodine crystals [closed]

I really don’t understand why the following reaction would take place first of all. So this is a sub part of a question wherein we have to compare the basicity of the compounds formed through some ...
0
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1answer
72 views

Is there a phase diagram available for hydrogen fluoride?

Has a phase diagram for hydrogen fluoride been published in an article on the internet or in a book ? Or is there a table for HF for different pressures up to 100 atm. and temperatures up to 500$⁰$ C ...
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3answers
75 views

What is the color of a FeS4O6 solution [closed]

What is the colour of FeS4O6 solution?!
3
votes
2answers
129 views

General justification for steady state approximation

I want to understand the assumptions that have to be fulfilled in order for the steady state approximation to work. I did some research myself and was able to deduce assumptions of the form $k_1\gg ...
0
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0answers
28 views

Temperature in Le Chatelier's principle [duplicate]

Suppose I have a reversible reaction and the forward reaction is endothermic. Now if I increase the temperature, the rate of the forward reaction will increase but as I increase the temperature, the ...
1
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0answers
34 views

How to assign initial and final states of iodine transitions in its spectrum?

In an experiment, I gently heated iodine crystals to create vapors and then observed it absorption spectrum with a spectrometer. The temperatures throughout were moderate (maximum $40^\circ\text{C}$). ...
1
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0answers
21 views

Relation between activating properties and directing nature

Why are activating groups not always ortho-para directing and decativating groups meta directing? For example, we have: Halogens which are deactivating, but ortho-para directing. Nitro group which ...
-3
votes
1answer
36 views

Chemical Formation Of A Virus [closed]

Many articles and books classify virus as a non living thing which only replicate itself inside a living host, yet some describe virus as a living organism. Virus was first discovered on the year 1892 ...
2
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0answers
43 views

Observing bands which I shouldn't be!

I performed the iodine spectrum experiment to observe vibronic transitions. I heated the iodine crystals to produce vapors (at a little above room temperature) and observed absorption spectrum with a ...
1
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2answers
89 views

Why does strength of bond matter if melting only affects the the intermolecular of the molecules

So as I've been told, when a substance melts, the actual bonds of the substance aren't broken, only the IMFs (inter-molecular forces). So why is it that metal groups decrease in melting points going ...
1
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1answer
58 views

Why is the voltage produced by a voltaic cell affected by temperature as described by the Nernst Equation?

I understand why changing the concentrations of the electrolytes in a voltaic cell affects the voltage. Given a zinc-copper cell for example, if I were to increase the concentration of the zinc ...
-1
votes
2answers
37 views

Why is the number of covalent bounds typically formed by an element equal to 8 minus the group number? [closed]

Why would the number of covalent bounds typically formed by an element equal to 8 minus the group number? E.g for C, we have 8-4 bonds, for Cl, 8-7 bonds
0
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1answer
47 views

Reaction of dimethyl sulfate with Protocatechualdehyde [closed]

I know that $\ce{(CH3)2SO4}$ reacts with phenols to give methoxybenzene. But the question that came in INChO-2018 was: When one equivalent of $\ce{NaOH}$ and one equivalent of dimethyl sulfate ...
2
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0answers
43 views

Mechanism of Etard reaction [duplicate]

According to Wikipedia Etard reaction proceed via a ene reaction with chromyl chloride forming a Etard complex(Chromium complex) which is then decomposed by a [2,3] sigmatropic shift to give aldehyde. ...
0
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1answer
24 views

Electrical and Thermal conductivity of electrum alloys

I have tried to search for this to little effect - I am trying to find electrical and thermal conductivity values for Electrum (a gold and silver alloy). Most sites mention the values depend on the ...
-2
votes
1answer
44 views

How to tell if an acid disassociate completely or partially? [closed]

what is the difference between and how can I tell which one is the stronger acid, base on the 2 equations?
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0answers
33 views

Why does a paracetamol tablet clean an iron [closed]

If you burn some clothes on an iron and some residue sticks to it, rubbing a paracetamol tablet over it (while it's hot) surprisingly removes the residue and cleans the iron. Please explain why this ...
0
votes
1answer
30 views

Why does Calcium (specifically Calcium Carbonate) inhibit the Citrate buffer system?

Is it because citrate chelates calcium and then is unable to react with other chemicals being added? If so can someone explain this reaction to me, or if not provide what the reason is? If anyone has ...
1
vote
1answer
52 views

Trends in solubility of group 2 nitrates

In my lab report, we are required to explain the trends in solubility of group 2 salts, going down the group. I had explained all of the trends except one, group 2 nitrates. The following is the data ...
-1
votes
1answer
51 views

A sealed container contains 90 % hydrogen and 10 % oxygen. There is a spark in the container. What happens? [closed]

A sealed container contains 90 % hydrogen and 10 % oxygen. There is a spark in the container. What happens? Assuming it is a 10-litre volume container like a fuel tank.
4
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0answers
76 views

What is it that makes this noncontact catalytic system unique in 2020?

Phys.org's Accelerating chemical reactions without direct contact with a catalyst discusses the new Science Advances paper Noncontact catalysis: Initiation of selective ethylbenzene oxidation by Au ...
-2
votes
1answer
44 views

Why are borates more stable than aluminates? [closed]

In the differences between Boron and Aluminium, it is given that boron forms stable Borates and Aluminium forms unstable aluminates . Please explain the stability of the 2 compounds.
1
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0answers
43 views

Data-processing pipeline for protein x-ray crystallography: uncertain of terminology and order of procedures [closed]

Background: I am trying to get an overview of the data-processing pipeline for solving protein structures by x-ray crystallography, and in a very simple way understand what mathematical procedures are ...
0
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1answer
42 views

Is cis- or trans-cycloundecene more stable? [duplicate]

While reading about cis/trans isomerism in cycloalkenes, I came across the following statement: When the number of carbon atoms in a cycloalkane is less than 11, the cis form is more stable than ...
-1
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0answers
20 views

PEO dissolved in deionized water and then cooled

I am looking to dissolve PEO (Mw ~ 300,000) that has a melting point of around 60 degrees C. I am planning on heating the DI water to 50 degrees and gradually dissolve the PEO in. However, if I let ...
-1
votes
2answers
85 views

Antibacterial properties of Ethanol and Isopropanol [closed]

Ethyl alcohol is widely used in beverages, while isopropyl alcohol is commonly sold as an antiseptic. However, some use both ethyl alcohol and isopropyl alcohol as antibacterial protection. I am ...
-1
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0answers
59 views

What is Baker Nathan effect?

The following statement is from Solomons, Fryhle and Snyder Organic Chemistry: In 1935, Baker Nathan effect explained that hyperconjugation dominates inductive effect. [...] The electron donation ...
5
votes
1answer
137 views

How to determine the relative contribution of resonance structures when different rules give contradictory outcomes?

In order to determine the relative contributions of resonance structures, my textbook gives the following rules (in order): The more covalent bonds a structure has, the higher it scores. Structures ...
0
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0answers
14 views

How to compare stabilities of the following carbocations? [duplicate]

I know that hyperconjugation is an important factor in determining carbacation stability but all of them have only 1 alpha hydrogen next factor should be inductive effect i think can anyone tell me ...
1
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0answers
46 views

How to dissolve salicylic acid into a solution with humic acid [closed]

I'm not a chemist but I am trying to make a product to be used as a foliar spray on turfgrass for my own use. The product I'm trying to make is: 12% Humic acid ($\mathrm{pH =}$ 3.5-4.0) 2% Fulvic ...
4
votes
1answer
50 views

When non-polar particles interact through dispersion forces, how fast does a temporary dipole induce a dipole in the neighboring molecule?

The current question is inspired by this existing question: At what frequency does a non-polar molecule acquire a dipole able to participate in London Dispersion forces?. In the comments and answers, ...
0
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1answer
63 views

Which has a lower boiling point, Ozone or CO2? Why?

Ozone is a bent molecule, and therefore, Ozone is a polar molecule. Polar molecules have dipole-dipole intermolecular forces. CO2 is a linear molecule, and therefore, CO2 is a nonpolar molecule. ...
0
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0answers
28 views

What is the result of the combustion of the mixture?

I prepared a little experiment about solid rocket propulsion. I have used water ($H_{2}O$), potassium nitrate ($KNO_{3}$) and saccharose ($C_{12}H_{22}O_{11}$). I made the mixture in a pan by cooking ...
4
votes
1answer
668 views

Understanding @ symbol used in material science

Hello I'm trying to do some research and came across the phrase "Silicone Rubber/Paraffin@Silicon Dioxide" also written as $\ce{SR/pa@SiO2}.$ Any help in understanding what this means is greatly ...
-1
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1answer
61 views

Determine H, q, w, and E at 298 K and 1 atm for the complete reaction of 8.170 g of N2O4.?

Determine $H$, $Q$, $W$, and $E$ at $298\ \mathrm K$ and $1\ \mathrm{atm}$ for the complete reaction of $8.170\ \mathrm g$ of $\ce{N2O4}$. $$\ce{N2O4(g) + 2N2H4(l) -> 3N2(g) + 4H2O(l)}$$ ...
0
votes
0answers
44 views

How to determine the expression of polytropic specific heat and the rule of polytropic transformation? (Thermodynamics)

This is how i manage to solve this question, any feedback is welcome. Also, if you feel that this is not easy understandable, feel free to add comments. I will drop a link to this file in my drive. ...
0
votes
0answers
43 views

How to test for methane gas purity?

I use methane gas for cooking and there are times in which, despite burners being clean, the flame doesn't burn that well and/or is quite red. I suspect that said gas actually has some air added in, ...
-2
votes
2answers
48 views

Reason for Exothermic reaction? [closed]

Why dissolving sodium hydroxide in water is an exothermic process. What causes the evolution of heat when dissolving sodium hydroxide in water?
0
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1answer
46 views

Is “family” synonymous with “group”? [closed]

Is using the term "family" strictly correct when we mean a group of the periodic table or is it just in general use (and should perhaps be discouraged in favour of using "group" exclusively)? At my ...

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