0
votes
0answers
7 views

Why do Ionic Compounds have Larger Melting Points/Boiling Points when they have smaller radii?

The title says it all, I thought it should be that the closer the two ions are, the larger the repulsive force, therefore, it should rather require less energy to take them apart (although being too ...
4
votes
1answer
28 views

Trying to understand SMILES patterns?

In the example calculation from the conformer search package fafoom is a mysterious pattern that I'd like to understand. The SMILES code of the given example structure is: ...
1
vote
0answers
25 views

What is the degradation mechanism of pyrrole?

A vial of pyrrole monomer (that was occasionally exposed to air) changed its color while degrading from pale yellow to dark orange. What is the mechanism of pyrrole degradation? What are the ...
1
vote
0answers
12 views

Relationship between vapour pressure and saturated vapour pressure

I need clarity on saturated vapour pressure in a closed system at equilibrium. How does saturated vapour pressure relate to vapour pressure?
2
votes
1answer
15 views

Why is it possible to use lipids to recover diamonds in mining?

Diamond mining This link says that diamonds will stick to "anything oleaginous" and that other materials slide down the fat that is applied to an inclined plane used in the mining apparatus. I infer ...
2
votes
1answer
15 views

Reaction between a vinegar/salt/hydrogen peroxide mixture as an etching solution and copper

I am looking for the less harmful chemical solution to serve as an etching solution. After many searches, my interest went to a vinegar/salt/hydrogen peroxide solution. I have to ask then if the ...
3
votes
0answers
13 views

Electrical properties of 2D materials

This is regarding to the newly-discovered 2-D materials that can support electron flow, such as phosphorene and transition metal dichalcogenides. How do they conduct electricity? I also read that ...
1
vote
0answers
9 views

Do ion-exchange resins soften water through a kinetic equilibrium process?

I searched a lot for this and couldn't find any answers. Is water softening a purely ratio-based equilibrium process, ie, more $\ce{Na+}$ cations on resin than there are $\ce{Ca^2+}$ cations in the ...
4
votes
1answer
33 views

Guess the shape and phase of the MOs of butadiene using LCAO and Hückel's method?

I used Hückel's method along with a Linear Combination of Atomic Orbitals (LCAO) to calculate an estimate for the orbital energies of cyclobutadiene ($\ce{C4H4}$) and butadiene ($\ce{C4H6}$). For ...
0
votes
1answer
10 views

Is it possible for monobasic and dibasic potassium phosphate to complete break down into phosphates?

Here is the picture of monobasic potassium phosphate: And here is the picture of dibasic potassium phosphate: Is it possible for the phosphorous-containing anions to further break down into ...
1
vote
0answers
12 views

Quenching rates in nucleation MD simulations

I am trying to perform nucleation simulations with molecular dynamics. To prepare the metastable fluid, I am equilibrating at temperatures about 30 K above the melting temperature, and then ...
1
vote
1answer
13 views

Numbering heteroatoms and groups in benzene derivatives

Can someone please explain why the carbon in 8-hydroxyquinoline is numbered 8, while in 1,10-phenanthroline the nitrogens are numbered 1 and 10? I'm counting carbon atoms and just cannot see why the ...
2
votes
1answer
22 views

Confused about writing out electron configurations

I watched the Crash Course chemistry video about the electron. In the video Hank showed an example configuration of iron as $\mathrm{(1s)^2 (2s)^2 (2p)^6 (3s)^2 (3p)^6 (4s)^2 (3d)^6}$ and explained ...
-4
votes
0answers
28 views

Chemical Reactions [on hold]

**Hello! I would like to ask about informations about chemical reactions. You could use this as a guide. Thank you. Synthesis Reactants: two or more elements or______?(compounds are joined together) ...
0
votes
0answers
40 views

boiling water function

I want to make a program that realistically simulates boiling water with all the variables. One of my problems is that I know near nothing about the math behind it. So far I got the energy transfer ...
6
votes
2answers
475 views

Ideal Gas Equation Contradiction [duplicate]

You have a regular balloon, and you decide to heat it up. The gas particles inside the balloon will gain kinetic energy, and so, the gaseous particles will collide with the internal wall of the ...
2
votes
1answer
30 views

Le Chatelier's Principle and Rate constants

I am confused about the application of Le Chatelier's principle to reaction systems. Consider the reaction: $$\rm H_2O_2 (g) \rightleftharpoons 2\, OH^{.} (g)\,\,\,\,\,(i)$$ to be at at equilibrium. ...
6
votes
2answers
51 views

Why does concentrated HCl fume?

It is a common observation that a concentrated solution of hydrochloric acid kept in the lab fumes. What is the chemistry behind this phenomenon? Does $\ce{HCl}$ somehow react with the moisture in the ...
2
votes
0answers
36 views

What happens when two nitrates react with each other?

I am trying to determine the products of the ammonium nitrate and copper nitrate. Any ideas on if the below reaction is correct? $$\ce{NH4NO3 + Cu(NO3)2 -> Cu(NH3)4(NO3)2}$$ Ammonium Nitrate + ...
2
votes
0answers
23 views

Few basic questions about ionic bonding and batteries (lead)

I've got a few very very basic questions about ionic bonds and their role in batteries. My assumptions (correct me if I'm wrong): Ionic bonds occur between a metal and a non-metal (the non-metal ...
0
votes
0answers
16 views

Energy Transfer in Breaking Chemical Bonds

When discussing the electrolysis of water: what are observations during the electrolysis that illustrate that energy transfer is involved in the formation or breaking of chemical bonds.
0
votes
0answers
22 views

C-O vs. C=O ionic percentage [on hold]

Why is a carbon monoxide single bond less ionic (10% ionic character) than a carbon monoxide double bond (41% ionic character)?
3
votes
0answers
11 views

Molecular differences in the HB graphite hardness scale

Today, I bought some graphite for my pencil. It is rated HB on the HB graphite scale, a measurement of the hardness of graphite. My question is how can there be different hardnesses of the same ...
-1
votes
0answers
18 views

Make a sketch of SCl6 and IF4+ [on hold]

Draw the molecule by placing atoms on the grid and connecting them with bonds using the straight line, hatched wedge and solid wedge 3D format. Please show the formal charges of $\ce{IF4+}$
3
votes
1answer
37 views

How does the acidity of soft drinks not affect certain drugs, such as opiates? What about drugs and stomach acid?

Here's a very random introduction. I heard the term, "dirty Sprite" (it's some rap album/slang term) on a YouTube advertisement. I Googled "dirty Sprite", and it's apparently a recreational drug: ...
-3
votes
0answers
24 views

Calculation of Calorimeter Constants [on hold]

$\mathrm{100~g}$ of water at $\mathrm{45~^\circ C}$ is added to $\mathrm{100~g}$ of water in a calorimeter at $\mathrm{20~^\circ C}$. The temperature of the mixture is $\mathrm{30~^\circ C}$. ...
0
votes
1answer
30 views

How do I determine the composition of an unknown substance? [on hold]

If I have a product - for example, synthetic chicken feed - for which I want to determine the composition, what type of lab would I go to? What is this process called? How much does it usually cost?
1
vote
1answer
30 views

Do electrons in covalent bonds always obey the octet rule? [duplicate]

Do electrons in covalent bonds always necessarily obey the octet rule? Always?
1
vote
1answer
19 views

Do Slater's rules apply to neutral lithium (at least approximately)?

For lithium, the electronic configuration is $\ce{(1s)^2(2s)^1}$. I tried to calculate $Z_{eff}$ for the $\ce{2s}$ orbital of the neutral atom as follows: $$Z_{eff} = Z-\sigma$$ $$Z_{eff} = ...
1
vote
0answers
13 views

Why does the dielectric constant of a solid increase due to a Frenkel defect?

In crystalline solids, an atom may be displaced from its original position in order to create a vacancy in the original location. This is referred to as a Frenkel defect. Why does this defect result ...
2
votes
1answer
21 views

Why is the formation of double helix between non complementary sequences disfavoured?

The textbooks starts with the phenomena that double helix is an expression of the rules of chemistry. Hydrogen bonds are important in determining the formation of specific base pairs in the ...
4
votes
0answers
24 views

Hydride shift reaction

How is this hydride shift reaction type called? I think it's not one of following types: cycloaddition (Diels Alder) electrocyclic ring opening sigmatropic rearrangement ene reaction cheleotropic ...
1
vote
0answers
10 views

ASTM Viscosity Index Formula/Table derivation

How was the ASTM formula for Viscosity Index derived? Specifically with reference to the reference oils considered and the table for it. The viscosity index can be calculated using the following ...
5
votes
0answers
31 views

How are solubilities of hydrate salts determined when competing equilibria are unavoidable?

When you calculate the solubility product constant for a salt and one of its hydrates, you sometimes get drastically different numbers! I don't know how this can be because they both dissociate into ...
2
votes
1answer
78 views

How Many mL of 1.0M HCl Would be Required to Completely Decompose Sucrose into Glucose and Fructose?

I am currently conducting an experiment into the glucose content of certain sports drinks. However, I have hit a roadblock. A majority of the drinks that I intend to test contain sucrose. I am ...
2
votes
1answer
36 views

What is the stochiometric equation of the sucrose and potassium chlorate reaction with sulfuric acid?

I am researching this reaction for my chemistry assessment. Various sources I have dug up state different answers and opinions on what the stoichiometry is and what the products are, sometimes giving ...
0
votes
0answers
29 views

What Chemical Trigger Causes Ectomycorrhiza To Change From Asexual To Sexual? [on hold]

I am searching for the catalyst behind the change of asexual to sexual ectomycorrhiza when symbiosis with a tree root is formed. As ectomycorrhiza attaches itself to a root, they form a relationship ...
1
vote
1answer
55 views

Can Aluminum and HCl be used to generate hydrogen gas

I am looking to produce hydrogen gas in a small amount with supplies I currently have. Most of the methods I have seen involve reacting zinc or magnesium with HCl to obtain the gas, but I do not have ...
7
votes
1answer
203 views

Do aromatic dienes undergo the Diels-Alder reaction?

Do aromatic dienes undergo Diels-Alder reactions? My understanding is that the $\pi$ bonds in aromatic compounds are not as localised as they are in other compounds, such as aliphatic dienes. ...
0
votes
0answers
33 views

How does the following work in Alkyne?

I have the following reactions from a book, but it is not explained how the different substances come into being. I don't know what happens to $\ce{3H2O (H3O)}$ in the second line.
3
votes
0answers
24 views

What is the cause of hygroscopy?

Hygroscopy is the ability of a substance to attract and hold water molecules from the surrounding environment. Why are some compounds hygroscopic and others are not? What is it about their ...
2
votes
0answers
43 views

Question about theoretical modeling of photocatalysis

As a computational materials chemist studying photocatalysis, how close to realistic systems can your modeling get? I have a sort of high-level question about the theoretical modeling of ...
2
votes
1answer
42 views

Finding average half life of radioactive nuclide which undergoes two different decays

Find the average life of a radio nuclide which decays by parallel paths $$A\rightarrow B$$ $$2A\rightarrow B$$ where the decay constants are $\lambda_1=0.018\ \mathrm{s}^{-1}$ and $\lambda_2=0.001\ ...
-1
votes
0answers
24 views

Source of problem sets for mit open course [on hold]

I was wathcing the 5.111 principles of chemical science lectures(@ ocw.mit.edu) and i wondered where i'd get the problem sets that they were mentioning. Is it available online? I would like to do the ...
2
votes
1answer
44 views

How could a rechargeable battery recharge itself?

I'm an engineering student preparing for my graduation, in one step of my graduation project I used a rechargeable battery(1.2 volt), i was shocked when this battery is starting to recharge it self ...
2
votes
1answer
26 views

Calculating Molar Volume from crystal volume

I am trying to calculate molar volume of certain crystal lattices to be used for crystal growth kinetics calculations. The information I have is the crystal volume & crystal lattices. For example ...
2
votes
1answer
32 views

Why is microcosmic salt called so?

I really see no relation between the terms microcosmic and the salt's structural formula, $\ce{Na(NH4)HPO4.4H2O}$. Devoting sufficient time on Google didn't help at all. Information about the name ...
0
votes
0answers
21 views

Converting sodium lauryl sulfate into a powder

I need to turn sodium lauryl sulfate into a powder form. I have the substance in a gel form, and I tried mixing it with corn starch to dry it out but I failed. Any ideas on what to do?
4
votes
1answer
33 views

How to Convert Sucrose to Glucose and Fructose

If you have some sort of sports drink that contains sucrose, how would you take that sucrose and break it down into its components, glucose and fructose? I know that sucrose + water will break it ...
3
votes
1answer
55 views

Le Chatelier's Principle: What does temperature do gas concentrations?

I am confused about a specific part of Le Chatelier's Principle. My question revolves around a homework assignment question: $$\ce{2SO2(g) + O2(g) <=> 2SO3(g)} \qquad\Delta H^\circ = ...

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