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0answers
23 views

When is the density of a mixture just the sum of the densities of each species in the mixture? [closed]

My current hypothesis is that this is true when the volume is finite and perhaps this would cause the densities to be additive. Also, when would you find mixture density using $$ \frac{1}{\rho} = \...
1
vote
1answer
25 views

Why is the formation of the nitro isomer more favorable under acidic conditions

In the reaction between chloropenataamminecobalt and nitrite either the NO2 or the ONO linkage isomer is formed. This preference seems to be mainly due to the pH of the solution with acidic conditions ...
0
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0answers
9 views

How would an aromatic current behave in a graphene quantum dot?

Aromatic current in macrocyclic compounds is always planar to the aromatic structure, but in a graphene quantum dot, the structure would no longer be one dimensional. Would this affect the aromatic ...
0
votes
1answer
23 views

why do we need to assign ΔH =0 for the formation of aqueous hydrogen ions?

Many books state that the enthalpy of formation of aqueous hydrogen ions is 0 BY DEFINITION, and hydrogen is chosen just for convenience. Once we do that, all other reactions have their enthalpies ...
9
votes
1answer
338 views

Tin(II) chloride electrolysis problems: (1) Why is the tin dendritic? (2) Why does the unconnected metal in the middle also act like an electrode?

I'm watching this tin(II) chloride electrolysis video: https://www.youtube.com/watch?v=coPGazAaVBE&ab_channel=FlinnScientific Two phenomenon puzzled me, and I couldn't find a good explanation on ...
1
vote
1answer
35 views

How to "draw" a coordination bond (dashed bond) in MOLFILE?

How can we "draw" a coordination bond (dashed bond) in MOLFILE? I cannot find a bond property or option that would allow me to choose such a thing. So many drawings of organo-metallic ...
-1
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0answers
23 views

How does this work? [closed]

Could someone please explain this to me, it does not make sense I do not understand how this works, how can you be sure the product formed is exactly 60 dm^3. I know the product is two times the O but ...
-4
votes
0answers
13 views

How to calculate the temperature when equipartition is estimated [closed]

what must be the temperature be before the energy estimated from equipartition theorem is within 2 percent of the energy given. please help me to solve this. E= hcv/e^(bhcv)-1 v is the wavenumber is ...
2
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0answers
17 views

CVD MoS2 always get many particles/stuff on the surface, what is problem?

The $\ce{MoO3}$ and $\ce{SiO2}$ substrate is placed in the center of furnace and sulfur boat is in the upstream out of the furnace. In a general growth: $\approx \pu{2 mg}$ $\ce{MoO3}$ and $\approx \...
10
votes
1answer
1k views

What happens when I use cyclohexanol to prepare cyclohexene?

I've done a student experiment using cyclohexanol to prepare cyclohexene. We mix $10.5~\mathrm{g}$ cyclohexanol and $5~\mathrm{mL}$ $85\%$ $\ce{H3PO4}$ in a $50~\mathrm{mL}$ flask, then distill while ...
0
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1answer
3k views

Polarity and stability

Why is cis-1,2-cyclohexadiol less polar than trans-1,2-cyclohexadiol? I know it has something to do with stability and chair conformations, but I'm not sure how it relates to polarity. I know cis-1,...
0
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0answers
29 views

How to know the wavelength if the number of spectral emission lines is given? [closed]

A sample tube consisted of atomic hydrogen in their ground state. A student illuminated the atoms with monochromatic light, i.e. light of a single wavelength. If only two spectral emission lines in ...
-4
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0answers
44 views

Anti-Stokes percent [closed]

What are some examples of things that have a highest % of anti-Stokes shifts, in Raman scattering? (To clarify this is not a personal attack on Mr. Stokes, or anyone with the last name Stokes...).
1
vote
0answers
20 views

Galvanic corrosion in heating system

I’m a training heating engineer and have am unsure on hydrogen build-up in heating systems. I understand that any free air and the water within a heating system will react with the iron content in ...
1
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0answers
43 views

Why electron configuration of thulium is $[\ce{Xe}]~\mathrm{(6s)^2(4f)^{13}}$ instead of$[\ce{Xe}]~\mathrm{(6s)^1(4f)^{14}}$?

We know that half-filled or full filled orbitals are more stable. That's why the ground state electron configuration of gadolinium is $[\ce{Xe}]~\mathrm{(6s)^2(4f)^7(5d)^1}$ rather than$[\ce{Xe}]~\...
0
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0answers
16 views

Can a damaged neoprene (polychloropren) or rubber coating be cured (hardened) using a hot air gun and a curing agent?

Polymers can be hardened by a process known as vulcanization (curing of elastomers), a chemical process that involves a curing agent and heat. According to Wikipedia, for the vulcanization of rubber, ...
-4
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0answers
19 views

Do we need to memorize the formula of water H2O? Why is water H2O? [closed]

Before anyone answers my question, I want to tell you something: I have zero knowledge of chemistry, which means no knowledge. So, it's the first question that came to my mind! Could anyone please ...
2
votes
2answers
106 views

How do I obtain a 3D MOLFILE for the lactose synthase structure, especially the catalytic center?

So for example there is a paper by Ramakrishnan and Qasba which presents a model in a 3d stereo picture it has UDP-Gal, Glc, Mn++, a piece of the lactalbumin protein (?) and a piece of the lactose ...
-1
votes
1answer
25 views

Does pressure affect rate constant? [duplicate]

I would like to know if pressure affects rate constant. Suppose pressure affects the rate constant. Does it depend on partial pressure (like: if I add an inert gas to the system), or only increasing ...
0
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0answers
50 views

Are there any chemicals or drugs that create negative affects like depression for example, opposite of what painkillers do?

I recently saw a comic where this rich guy literally smokes depression, like in a cigar. He said that the relief felt after it wore off was better than any high out there. While I don't ever plan on ...
1
vote
0answers
35 views

What do sequence numbers in PDB files actually mean and why don't they match the sequence?

I am studying the 3D structure of the LDH from x-ray crystallographic imaging I was pointed to from Is there any stereospecific enzyme in PDB that catalyzes an anabolic reaction and has an entry ...
-2
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2answers
67 views

How do you know is a solution is acid or basic when you dissolve a weak acid/base? [closed]

If I dissolve the weak acid HCN into water, I get a solution of oxonium and CN ions and since there is an equilibrium there is more HCN left. So I thought CN ions can consequently react with water to ...
0
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0answers
23 views

Hazards of eating non-stick coating, particularly considering the coating primer

How unhealthy are teflon / non-stick coating chips that end up eaten? What role does the primer coating play? Existing similar threads that don't go into enough detail: 1, 2 I understand that there is ...
-3
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0answers
18 views

When an atom loses an electron to become an ion, where does the electron go? [closed]

Similarly, if an atom were to gain an electron to become more stable, where would it gain the electron from?
0
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0answers
14 views

How to experimentally measure ground state energy of molecules [closed]

How can one calculate the ground state energy of a molecule (an energy corresponding to ground state Hamiltonian of molecule, theoretically speaking). Can you please explain. Thank you.
1
vote
3answers
71 views

Where are orbitals located in an atom? [closed]

I am having trouble understanding what are the orbitals. Till now what I have understood, I have depicted in this diagram. Is the diagram correct?? If not, what should be the corrections?
-2
votes
0answers
16 views

Factors affecting rate constant of a chemical reaction [closed]

I am trying to understand the rate constant correctly, some sources seem to be giving different answers so I just want to clarify some factors that may affect the rate constant A) temperature B) ...
0
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0answers
43 views

Aluminum cathode in electrolysis

I am using electrolysis to clean and remove rust from carbon steel parts. For the anode I use sacrificial carbon steel. For the cathode I use the steel part I am cleaning. The electrolyte is a ...
-3
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0answers
35 views

Hi! I have questions about chemical reactions [closed]

Hi working on a film where we do a fake chemistry set up and must produce crystals quickly - any suggestions ? Must be safe for actors
2
votes
0answers
16 views

Appearance of drying hemoglobin-and-salt droplets

I initially posted these or similar images at the bio site because they looked to me like organic/mold contamination in a slide (low power) containing hemoglobin and salt. As the slide dried these ...
6
votes
1answer
178 views

How does a spectrophotometer measure absorbance based on the intensity of detected light?

We know that $\displaystyle A = -\log\frac{I_t}{I_0}$, where $I_0$ is the intensity of light without a sample absorbing, and $I_t$ with the sample. For determining the absorption $A$, we need both $...
-2
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0answers
16 views

How can I solve for the q and the change of enthalpy [closed]

You place 50.0 mL of 0.500 M NaOH in a coffee-cup calorimeter at 35.00oC and add 25.00 mL of 0.500 M HCl, also at 35.00oC. After stirring, the final temperature is 37.21oC. [Assume the total volume is ...
-4
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0answers
37 views

Just negatively charged or another element? [closed]

Good evening! So I’ve been wondering if I took a proton away from an Iron atom (26 protons), it would have 25 protons left.. Would it just be a negatively charged iron atom or would it be a manganese ...
-2
votes
0answers
9 views

Acid base titration [closed]

A is a solution of trioxonitrate (v) acid of no concentration. B is a standard solution of sodium hydroxide containing 4 gram per dm³ of solution. 25cm³ of portion of solution B require an average of ...
-2
votes
0answers
17 views

Heavy Organics Heat Exchanger Design 1-Butanol [closed]

Is 1-Butanol (Bultyl Alcohol) classed as a heavy organic?
2
votes
2answers
80 views

Can LaCl3, FeCl3 be used as a "Lewis Acid" substitute for AlCl3 in Friedel-Crafts reaction?

AlCl3 is a Lewis acid. In Friedel-Craft reaction, purpose of AlCl3 is to produce electrophile, which later adds to benzene nucleus. This electrophilic aromatic substitution allows the synthesis of ...
2
votes
2answers
79 views

Clarification of term symbol explanation of laser crystal doping from textbook

I am currently studying the textbook Diode Lasers and Photonic Integrated Circuits, second edition, by Coldren, Corzine, and Mashanovitch. Chapter 1.2 ENERGY LEVELS AND BANDS IN SOLIDS says the ...
-1
votes
0answers
8 views

How will the addition of water affect equilibrium in the following reaction? [closed]

2Al(s) + 2NaOH(aq) + 6H2O(l) ⇆ 2NaAl(OH)4(aq) + 3H2(g) What characteristic does the reaction need to have in order to favor hydrogen production when temperature is increased?
-1
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0answers
36 views

Calculating pH of weak acid considering hydronium ions from water

In general to calculate pH of a weak acid , if we have $c$ concentration of acid initially then at equilibrium $\ce{H3O+}$ concentration is said to be $c$$\alpha$ , but I wanna ask that doesn't $\ce{...
0
votes
1answer
36 views

Purpose of Sodium Fluoride (NaF) in Sodium Hydrogen Sulphate (NaHSO4) acid pickling solution?

I am a proud home workshop electroplating fanatic, and the kit I sourced (from another country, with five weeks shipping) contained this bag of "Dry acide salts". I'm trying to source the ...
-1
votes
1answer
45 views

Attempting to make Rochelle salt but obtained paste

I was attempting to make Rochelle salt by adding sodium carbonate to a mixture of cream of tartar and water, but ended up with a solid paste. I kept the cream of tartar/water mix boiling the whole ...
-1
votes
0answers
31 views

Is the answer of this question wrong? [closed]

Today I stumbled upon a question which I found here. The following question given below consist of an Assertion and Reason type questions. Use the following key choose the appropriate answer. ...
-1
votes
1answer
36 views

What does valence electron mean (in the context of spdf orbitals)?

For a little bit of context, my background is in physics and my understanding of chemistry doesn't go past, say, middle school level. Recently, I decided to self-study chemistry and picked up "...
1
vote
3answers
2k views

Is Ammonia (NH3) base?

In my text book, it is written that $\ce{NH3}$ is a base. They mentioned the reason for this is that it produces $\ce{OH-}$ ions in water. They stated this reaction: $\ce{NH3 + H2O -> NH4OH}$ So ...
0
votes
0answers
26 views

Why does the pi3 MO of octatetraene look like this? [closed]

How it's drawn usually: Can I draw it like this instead? If not, what is a systematic way to derive where the nodal planes are located? Why must it be like 2, 4, 2 and not 3, 2, 3?
0
votes
0answers
43 views

Why is C-S-C bond angle in thiirane so small at 48.5 degrees?

Why is the C-S-C bond angle in thiirane (48.5 degrees) so much smaller than C-O-C bond angle in oxirane/epoxide (60 degrees). Source: https://coek.info/pdf-three-membered-ring-heterocycles-.html
0
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0answers
37 views

Name for long chain of double-bonded carbon atoms

Long ago (over 10 years), I read an article in my father's copy of Chemistry World on a substance consisting of many carbon atoms in a chain double bonded to each other: $$\ldots\ce{=C=C=C=C=C=}\ldots$...
-1
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0answers
26 views

Is it possible to make strong acids using (relatively) weak acids? [closed]

One of the routes of making hydrogen chloride involves heating a mixture of sodium bisulfate and sodium chloride. Considering that the equilibrium is constantly forced to shift to the right by ...
1
vote
0answers
50 views

What are orbitals? Am I correct? [closed]

I was having trouble to understand what orbitals are. What I have understood I have written below. For H atom at $n=1$, the electron can be anywhere, but at an instant $t$, the most probable location ...
-3
votes
0answers
11 views

Will the ability to pull the electrons toward the most electronegative atom decrease with number of bonds? [closed]

Could it be thought that with higher number of bonds an atom form, the more its electronegativity will decrease? Let us take oxygen as an example, which is a really electronegative atom and usually ...

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