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0answers
285 views

Comparing two oxidizing agents using electron configuration

Which oxidizing agent from the pair $\ce{K_2IrCl_6/K_2PtCl_6}$ is stronger? Explain your answer using their electron configurations. We write the electron configurations for $\ce{Ir/Ir^{4+}}$ and $\...
5
votes
1answer
1k views

How to calculate the dissociation constant of a weak acid from the titration with a strong base?

Problem: A solution of an unknown weak acid of unknown concentration was titrated with a solution of a strong base of unknown concentration. During the titration, the pH after adding $\pu{2.00 mL}$ ...
2
votes
1answer
464 views

Why does the acetyl group drop the pH? [closed]

I have a molecule that is 8% of the R groups are replaced with Acetyl groups. When I dissolve it in water it drops the pH. I am trying to understand why.
3
votes
0answers
213 views

Why do isomeric bis-ethylenediamine cobalt complexes react differently?

A compound $\ce{Co(en)2(NO2)2Cl}$ has been prepared in a number of isomeric forms.One form undergoes no reaction with $\ce{AgNO3}$ or $\ce{(en)}$ and is optically inactive. A second form reacts with $...
0
votes
1answer
891 views

Melting point-general chemistry

This one has stumped me for a few days. What is the specific name of the general chemistry principle that is responsible for the difference in melting points of pure and impure solids. I have ...
1
vote
0answers
57 views

Platinum vs Silver as Electrode for carbonic acid electrolyte [duplicate]

Is silver a better cathode electrode with carbonic acid in a galvanic cell or is a platinum electrode better with carbonic acid ? The anode electrode is copper with copper sulfate electrolyte, and the ...
4
votes
1answer
309 views

Can the first ionization energy for a specific element be calculated?

I'm taking a first-year Inorganic Chemistry course in college, and stumbled upon this problem: For $\ce{Mn}$ and $\ce{P}$, calculate the first ionization energy and explain the difference between ...
2
votes
2answers
416 views

Liquid that looks like smoke when bottled?

I am making a gift that will consist of a liquid in a sealed bottle. I want the liquid to have a magical appearance. Something like the appearance of smoke - varying opacity from almost clear to ...
1
vote
1answer
6k views

Positive vs. negative heat of solution confusion

Given that I have absolutely zero formal (or informal) education in chemistry (sorry about that), I'm struggling to get my head around what appears to be repeated confusions of the term "heat of ...
7
votes
2answers
13k views

Preparation of picric acid

My textbook says "Nowadays picric acid is prepared by treating phenol first with concentrated sulfuric acid which converts it to phenol-2,4-disulfuric acid and then with concentrated nitric acid to ...
1
vote
0answers
296 views

Replacing air with nitrogen in a drum.

I have a 55 gallon drum half ful of liquid. I would like to put a "blanket" of nitrogen over the liquid. How can I replace the air in the drum with nitrogen?
0
votes
0answers
92 views

How can be explained why the specific heat of ice is twice as low as liquid water?

To raise the temperature one degree of ice costs about 2000J but for liquid water it is 4000J. The reason for that is that the freedoms of vibrations rotation and translations of ice are lower and the ...
4
votes
1answer
248 views

Distinguishing among SN2/SN1/E1/E2 for a secondary bromide

a. 2-Bromo-3-phenylbutane reacts with $\ce{NaOMe}$ in methanol. What is the mechanism? b. This compound then reacted with $\ce{CN-}$ in DMSO. What is the mechanism? My Attempt a. I am debating ...
1
vote
0answers
43 views

Why do electrophillic addition reactions (between hydrogen halides and alkenes) happen?

I understand that the type of solvent (protic or aprotic) may impact the rate of the reaction, but why doesn't the hydrogen just stick with the halide in the first place? I'm not sure if the reason ...
15
votes
2answers
2k views

Thermodynamic and kinetic products - carbocation stability

The professor wants to know which is the thermodynamic product and which is the kinetic product. He says there are only two products - the two on the right that result from the resonance-stabilized ...
4
votes
1answer
368 views

Why did my deep eutectic solvent solidify?

I'm finally getting around to beginning to test this deep eutectic electrolyte. I mixed choline chloride with urea in a 1:2 mole ratio in a glass container. It formed a sludge. I sealed the ...
1
vote
1answer
5k views

Why is the enthalpy of solution for NaCl 3.88 and not 4.1 kJ/mol?

Based on Hess' law, the molar enthalpy of solution is equal to the sum of the enthalpies of formation of products minus reactants. In the case of dissolving table salt ($\ce{NaCl}$) in water, those ...
2
votes
1answer
89 views

How to dilute a stock solution when the resulting solution has a smaller volume? [closed]

Describe how you would dilute $2.0~\mathrm{L}$ of a $0.85~\mathrm{mol/L}$ magnesium hydroxide stock solution to make $200.0~\mathrm{mL}$ of $0.30~\mathrm{mol/L}$ magnesium hydroxide. I know the $$...
1
vote
1answer
148 views

Can I use fluorescence microscopy with a solution of hydrogen peroxide?

I want to use microspheres which have been dyed with a fluorescent dye for fluorescence microscopy in a solution that has a 1-5% concentration of hydrogen peroxide. Is this possible or will the ...
5
votes
2answers
5k views

Relative rates of two acyclic dienes in the Diels-Alder reaction

As for factors that affect the rate of the Diels Alder reaction, having an s-cis conformation is primary. But in a case as shown below, what makes the second diene react faster compared to the third? ...
2
votes
1answer
752 views

Stability of CN molecule

The $\ce{CN}$ molecule has been observed spectroscopically in comets where pressure has been estimated to be as low as $10^{-10}\ \mathrm{mmHg}$. Draw a Lewis structure for $\ce{CN}$. Suggest an ...
4
votes
1answer
8k views

What is the correct Lewis structure for calcium phosphate?

In calcium phosphate, $\ce{Ca3(PO4)2}$, since the calcium and phosphate share an ionic bond, and the phosphorus and oxygen share a covalent bond, should the Lewis structure be like the following? ...
2
votes
4answers
6k views

Sensitive test for lead in water?

Some of my friends are in Flint and I'm horrified by their situation. I would like to learn how to test for lead independently. After all if you can't trust the state sending them water to test is ...
0
votes
1answer
387 views

How many valence are in each molecule? [closed]

I have Benzene, Dewar Benzene, Prismane, and 1,3,5 cyclohexatriene (which looks just like benzene but with different lengths between the $\ce{C-C}$ bonds). They are all $\ce{C_6H_6}$ chemical ...
1
vote
1answer
242 views

Fermentation of different types of sugar

I'm searching for the difference in the fermentation of muscovado sugar, honey and sugar cane. I have used a specific microbiota to to ferment these three types of sugar and have to explain why I've ...
0
votes
1answer
2k views

Role of the counter/auxiliary electrode in cyclic voltammetry

I am doing a school project on cyclic voltammetry and am currently studying the topic. I have learnt that the reaction mostly takes place around the working electrode where the current is measured ...
6
votes
1answer
2k views

Increasing Covalent character increases Colour intensity

I observed some trends as follows:- $\ce{PbCl2}$ white and $\ce{PbI2}$ yellow $\ce{SnCl2}$ white, $\ce{SnCl4}$ red and $\ce{SnI4}$ black $\ce{AgCl}$ white, $\ce{AgI}$, $\ce{AgBr}$ and $\ce{Ag2CO3}$ ...
5
votes
1answer
3k views

Why is Hessian Matrix called 'force-constant' matrix?

Hessian Matrix is a square matrix containing the elements as the second-order partial derivatives of energy-function of a molecule; the derivative is done with respect to geometric coordinates of the ...
1
vote
1answer
196 views

If there is more than one branch in a hydrocarbon, which branch do you name first?

I have read that branches need to be named in alphabetical order, but I do not really understand this, or do you start with the branch closest to the edge of the hydrocarbon?
1
vote
1answer
323 views

When naming hydrocarbons, when do you number the branch or double bond? [closed]

I have realized that not all chains and double bonds are numbered. I have noticed that up until 3 carbons in a chain, the double bond is not numbered, but I am not sure about the chain.
5
votes
1answer
1k views

How does ice melt?

I know that when water freezes, it forms a crystalline structure created by the hydrogen bonds between polar water molecules. Also, I know that during a phase change, the potential energy of the ...
0
votes
0answers
1k views

why are cyclic dienes much more reactive?

Cyclic dienes are very reactive, for example cyclopentadiene in room temperature, it even dimerizes. What is the factor that indicates such reactivity of cyclic dienes ?
2
votes
1answer
145 views

Speed up polymerisation of formaldehyde

Is there a way to speed up the formation of para-formaldehyde in a formalin solution?
3
votes
1answer
111 views

Are elemental compounds composed of different isotopes polarised?

Are elemental compounds composed of different isotopes polarised? I'd expect any such effect would only really be noticeable for very light elements such as hydrogen. I'm not sure which way the ...
4
votes
2answers
16k views

Why do SN1 reactions prefer tertiary carbons?

I can understand that $\mathrm{S_N2}$ reactions prefer primary carbons, because of the steric hindrance that would be an obstacle. But what is the exact reason that $\mathrm{S_N1}$ reactions prefer ...
0
votes
0answers
125 views

Do SN1 reactions have dependency on the nucleophile?

'The rate of the reaction of tertiary butyl bromide with the hydroxy ion is dependent on the concentration of the tertiary butyl bromide, but is independent of the hydroxy ion.' This means that the ...
-1
votes
1answer
858 views

Why do SN1 reactions happen slowly?

'The first step where the carbonium ion forms is slow and because it contains only the halogen, the general speed of the reaction will be slow.' I don't understand why should SN1 reactions happen ...
0
votes
0answers
197 views

pH-dependency of the acidic dissociation of carbonic acid

I know the product of $\ce{CO2 +H2O}$ yields $\ce{H2CO3}$. This is a reversible equation so $\ce{H2CO3}$ goes back to $\ce{H2O + CO2}$. However, my question is: Is there a certain pH which will ...
1
vote
0answers
48 views

Non-standard source of lead?

Is there a way to get lead cheaply from local sources? I can buy ingots off eBay and there is a non-ferrous metal supplier I know who sells it for $12 for 5 pounds, but the shipping is nuts. I ...
2
votes
0answers
364 views

Infrared Spectroscopy of Hexachlorocyclotriphosphazene

When assigning the IR spectrum of hexachlorocyclotriphosphazene there are two prominent peaks (one due to the nitrogen-phosphorus bond and the other due to the phosphorus-chlorine bond). There is ...
-3
votes
1answer
244 views

Is this the correct formula for dopamine? [closed]

Google says that $C8H11NO2$ is the correct formula for dopamine. Is this so?
5
votes
1answer
680 views

How to extract water from a solution in formamide

I'd like to determine the water content in a sample without buying an expensive machine (like Karl Fischer titrator). So I'd like to measure the water volumetrically. I've chosen formamide to dissolve ...
15
votes
3answers
11k views

Why are acids usually depicted in fiction as green?

In cartoons, etc., acid is generally shown as vividly green, as in this scene from the Simpsons: We even have the colour "acid green". But when I used to use acids in chemistry class, they weren't ...
2
votes
1answer
998 views

How can I make my yeast experiment more chemistry-oriented? [closed]

For a school chemistry design lab I tried to find the optimal sugar concentration for fastest yeast fermentation. I put the same amount of yeast and sugar water solutions with different concentrations ...
6
votes
2answers
3k views

Dissolve Silver Oxide

I was looking at how to dissolve silver oxide (in a solvent). I know that monovalent silver oxide will not dissolve in water, but are there any solutions in which monovalent silver oxide will dissolve?...
5
votes
1answer
1k views

Does NH4 anion exist?

$\ce{BF3}$ can react with $\ce{F-}$ to give $\ce{BF4-}$ where we have for $\ce{B}$ in this molecule the 2s orbital and the three 2p orbitals filled totally (hybrid orbitals). In case of $\ce{NH3}$ ...
0
votes
1answer
5k views

Composition and pH of water produced by air conditioners

I would like to know if there are specific studies or research regarding the condensed water that is generated by air conditioners. Many people feel that this water is acid and corrosive but could ...
3
votes
2answers
2k views

Can carbon and titanium form an ionic bond?

Can carbon and titanium form an ionic bond because they both have four valence electrons? If titanium transfers four electrons to carbon, we get $\ce{Ti^4+}$ and $\ce{C^4-}$ which both have noble gas ...
3
votes
2answers
37k views

What factors could lower the voltage of a galvanic cell

Recently I conducted a lab in which the voltage of a galvanic cell between two metals was recorded. Both metals were placed in an solution of their own ions with nitrate and a salt bridge was made by ...
6
votes
1answer
156 views

What is the molecular structure of polymetatelluric acid?

Telluric Acid, $\ce{Te(OH)6}$, dehydrates to form polymetatelluric acid: $\ce{(H2TeO4)10}$. However, I have been unable to locate the exact structure of polymetatelluric acid, and it does not seem ...

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