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32
votes
2answers
9k views

Why does cyclopropane react with bromine?

In my exam, I was asked why cyclopropane could decolourise bromine water (indicating that it reacted with the bromine). All I could guess was that it is related to the high angle strain in ...
7
votes
3answers
61k views

Why do strong acids have weak conjugate bases?

This question is based on the Brønsted-Lowry model. I saw many answers to similar questions online. However none of them have given a detailed answer that is based on molecular structure (the answers ...
12
votes
1answer
528 views

What is the Structure of FeSO₄ • NO?

What is the structure of $\ce{FeSO4 \cdot NO}$ that is formed when $\ce{NO}$ is passed through ferrous sulfate solution? If it is a brown ring complex then why does the complex sphere break upon ...
2
votes
1answer
5k views

How do non-ionic compounds dissolve into water? Into molecules or atoms?

I can't seem to find the answer in google, which is surprising. I'm aware that ionic compounds dissolve into electrolytes. However, when non-ionic sacarose for example dissolves in water, does the ...
2
votes
2answers
5k views

What is Redox reaction? Is it really possible? [closed]

I was a reading a book that a senior gave me, it said that redox is a type of reaction in which both reduction and oxidation take place. I know about oxidation but not reduction. After googling ...
0
votes
1answer
642 views

How are Organic Compounds named? [closed]

I have heard of of a special system which specially deals with naming of organic compounds. How do we get names such as 2-methylpropan-1-ol. I have tried googling it and found few links but their ...
0
votes
2answers
723 views

How are electrons in conjugated molecules excited? [duplicate]

I have recently started reading about colour in organic molecules and come across conjugation of pi bonds. My question is pretty short... In transition metal ions I understand colour is caused by ...
9
votes
2answers
1k views

Normalization of the wavefunction φ(x) = A

I was trying to normalize the wave function $$ \psi (x) = \begin{cases} 0 & x<-b \\ A & -b \leq x \leq 3b \\ 0 & x>3b \end{cases} $$ This is done simply by evaluating $$ \int\...
2
votes
1answer
230 views

Nitrogen lone pair electrons on 2-acetyl-1-pyrroline

Please consider 2-acetyl-1-pyrroline: http://en.wikipedia.org/wiki/2-Acetyl-1-pyrroline What is the molecular geometry of the nitrogen lone pair? Is the lone pair oriented in-plane with the ring? ...
2
votes
1answer
574 views

Why do NaHCO₃ and KHCO₃ have different crystal structures?

Why do $\ce{NaHCO3}$ and $\ce{KHCO3}$ have different crystal structures? We had this in a test today and this got me stumped... My questions are: Do $\ce{NaHCO3}$ and $\ce{KHCO3}$ possess crystal ...
6
votes
1answer
3k views

Why is tetrathiocyanatocobaltate(II) blue?

Why is $\ce{Co(SCN)_{4}^{2-}}$ blue? I simply can't predict the colors of such inorganic salts. I have learned that $\ce {Co^{2+}}$ salts are pink in color. Also, if the ligand is a strong field ...
4
votes
3answers
2k views

Is there a mathematical generalization for the number of isomers (structural and configurational) of a given compound?

The original question was: How do I find the number of structural and configurational isomers of a given compound? is there any formula? For a specific example, how would I find the number of ...
2
votes
1answer
70 views

What type of material is this and how is it corroding?

So I was thinking about corrosion and I came across this structure(see image) Do you think the inner metal/alloy that is corroding is steel? Also, what do you think the outer layer (in white) is? ...
0
votes
2answers
720 views

Definition of nucleophile

I came across this definition. When discussing nucleophilicity we’re specifically talking about donating a pair of electrons to an atom other than hydrogen (usually carbon). When a species is ...
3
votes
0answers
901 views

Rationalizing Acidities of Ammonium Ion and Hydronium Ion

Stumbled across this interesting practice problem in my organic textbook. I have a few reasons for why $\ce{H4N+}$ is less acidic than $\ce{H3O+}$. 1) Let’s assess conjugate stability first. ...
0
votes
2answers
2k views

Mechanism of Acidity - Boric Acid [closed]

How does boric acid behave as an acid? Is it a Lewis acid or a Brønsted-Lowry acid?
2
votes
0answers
807 views

Cyclic Voltammogram - How to determine Overpotential

http://youtu.be/1f92vGOridg Clicking on the link above will take you to a video with a diagram of a voltammogram. Through my own experiments I have managed to obtain a similar diagram. However, I am ...
3
votes
2answers
3k views

Can a s orbital overlap with any p orbital to form a sigma bond?

In internet resources, only $p_z$ orbitals are shown to overlap with $s$ orbitals to form sigma bond. But my teacher says that according to Valence Bond Theory, $s$ orbital overlaps with all three $...
5
votes
1answer
2k views

The Acidity of the Hydrated Iron (III) Ion

Why is $\ce{Fe(OH_2)_6^{3+}}$ fairly acidic? This iron has six water molecules coordinated to it. In other words, water itself is a very weak acid. But when water is coordinated to iron, it becomes ...
1
vote
1answer
25 views

What is the correct temperature probe for a wet etch solution?

What type of probe or probe coating should one use to measure the temperature of a roughly 100c aqueous solution of cupric chloride? A stainless steel probe seems incorrect. Is a Teflon coated probe ...
0
votes
2answers
666 views

Does corrosion follow the law of conservation of mass?

For e.g .Due to rusting , iron becomes weak .So it should become weak only if the amount of iron is reduced. Even if we say the reduced iron is now the rust ,the amount of rust practically is very ...
2
votes
1answer
2k views

What is formed when hydrogen peroxide reacts with titanium?

I just got night contact lenses, and you are supposed to use a "one-step" cleaning solution to clean it over a period of six hours. At the bottom of the lenses case, there is a "titanium plate ...
1
vote
1answer
1k views

What are the factors that affect the corrosiveness of an acid?

Acids are usually corrosive but what determines this? Is it the concentration of the acid or strength of the acid ($K_a$ value)?
1
vote
2answers
432 views

Correct Electron Pushing with HCl and Water

My book indicates that the following electron pushing is wrong: So what would the right electron pushing diagram be? I have the following in mind. My rationale is: 1) Electrons attack protons, not ...
1
vote
2answers
2k views

Electron Pushing

I have a problem with this graphic, specifically the right hand side. Why a "sextet" atom (an atom with 6 valence electrons)? I thought only a select few elements (C, N, and O) actually follow the ...
2
votes
1answer
180 views

Nucleophiles and Electrophiles

Is ammonia a nucleophile and hydrogen the electrophile in the Brønsted-Lowry acid-base reaction of acietic acid with ammonia? I say that ammonia is the nucleophile because I drew a curved arrow from ...
0
votes
1answer
268 views

Equivalent Line Angle Structures?

Are the following equivalent structures for 2,2-dimethylpropane? I think so, because my rendering simply rotates the cross 45 degrees! Also, regarding 3,3-diethylpentane, are these both equally ...
3
votes
1answer
469 views

What is this red substance that has accumulated at the bottom of a plastic bottle full of petrol (see picture)?

About two weeks ago I put some ordinary unleaded petrol into a plastic water bottle, as a temporary measure (long story, don't ask!). It has now formed a reddish liquid at the bottom of the bottle. ...
0
votes
2answers
923 views

Line structure of formaldehyde

Would the line structure of formaldehyde, H2COH, simply be a straight line with a OH on the end of the line?
10
votes
1answer
213 views

Calculating Commutator of Differential Angular Momentum

I have tried for hours to calculate the commutator of angular momentum in the differential form, but I cannot get the correct answer. This is my first experience with actually checking if two ...
34
votes
1answer
3k views

Natural Bond Orbital analysis: Significance of stabilization energy determined by 2nd order perturbation

PREFACE: I am no expert on this topic. My questions at the bottom may be off base. I have some experience with symmetry-adapted perturbation theory (SAPT) when it comes to analyzing intermolecular ...
0
votes
1answer
384 views

Equivalent Cyclohexane Structures?

Are these structures equivalent? Image 1: http://i.minus.com/jnojtCx6wYvqD.png Image 2:
0
votes
3answers
989 views

What chemical test can differentiate secondary and tertiary alcohols?

I have to perform a chemical test to determine whether the solution is a secondary or a tertiary alcohol. How can I do this? Please explain the procedure and the apparatus.
5
votes
7answers
20k views

The solubility of haloalkanes in water

Haloalkanes aren't very soluble in water because they can't form hydrogen bonds, and the energy required to break hydrogen bonds in water etc is higher than the energy released when new bonds between ...
1
vote
1answer
833 views

How does carbonic acid cause acid rain when Kb of bicarbonate is greater than Ka?

How does carbonic acid cause acid rain when $K_b$ of bicarbonate is greater than $K_a$? Should it not create an alkaline solution? $K_a = 4.8 \times 10^{-11}\ (mol/L)$. $K_b = 2.3 \times 10^{-8}\ (...
2
votes
1answer
832 views

Which process is used to separate Hydrogen and Oxygen from Water?

What's the process called where you can use electricity to separate the oxygen and hydrogen from water? Is it electrolysis? Can it be applied to other liquids?
3
votes
1answer
2k views

Preparation of phenylamine/aniline

This is the procedure I carried out in class: Reduction of nitrobenzene by using tin and $\ce{HCl}$ acid After the completion of the reaction, $\ce{NaOH}$ added to neutralize excess acid and dissolve ...
2
votes
2answers
10k views

Ionizable hydrogen atoms for acids

Given that hydrogen atoms that are attached to a compound must be ionizable for the compound to be an acid, what prevents a hydrogen from being ionized? Is it solubility. If the bond is nonviolent, ...
-2
votes
3answers
2k views

Why are alkali and alkali earth metals indicative of a strong acid? [closed]

Why are alkali and alkali earth metals indicative of a strong acid? Does anyone know why it is so? Or tell me what is indicative of strong acids?
1
vote
3answers
8k views

Why is the reaction between hydroxide and water reversible, when the reaction between oxygen ions and water is not?

Why is the reaction between hydroxide and water reversible, when the reaction between oxygen ions and water is not? And is there a reason why the products of reaction 2) are written separately, ...
16
votes
3answers
981 views

Why doesn't the boiling point of an aqueous solution depend on intermolecular attraction?

I understand that boiling point is a colligative property for aqueous solutions, and that it empirically depends on the mole fraction of the solute, rather than the identity of the solute. I ...
3
votes
1answer
3k views

Vibrational Spectrums of HI, HBr, HF, and HCl

Do you all know of any large graphs for the vibrational spectrums of HI, HBr, HF, and HCl? I need graphs that are large enough to see the spacing between the peaks in the spectra of HCl, HBr, and HI. ...
16
votes
2answers
12k views

Why are vinylic and arylic carbocations highly unstable?

I have checked the internet and read quite a few books, but I still am not able to understand why vinylic and arylic carbocations are highly unstable. What I found while surfing the internet is: For ...
3
votes
2answers
31k views

Distinguish between symmetric and asymmetric molecules with IR

I get increasingly nervous as I get my organic lab course reports. For, I often get asked whether the peak in the IR comes from an asymmetric or symmetric stretch. I've looked at about ten books and ...
1
vote
2answers
2k views

Identify this ion

These are the results I got for my experiment. I'm having trouble interpreting the results. As you should be well aware of, Lithium and Strontium both burn with crimson red when they are placed in a ...
0
votes
1answer
155 views

An example to illustrate the difference between an inversion operation and a twofold rotation

Reading in Atkin's Inorganic Chemistry book, I cam accross: Although an inversion and a twofold rotation may sometimes achieve the same effect, that is not the case in general and the two ...
-2
votes
4answers
143 views

How can one come to know how a catalyst affects a reaction when the reaction and the catalyst is known [closed]

How can I come to know how a catalyst affects a reaction when the reaction and the catalyst used is known. I searched the internet for an answer but could not find one.
0
votes
1answer
206 views

Removing diamonds from a 14 karat gold ring with acid

I have a 14 karat gold ring with diamonds. I want to weaken the metal (to get the diamonds out without damaging them). If I dip the ring in sulfuric acid, will I be able to dissolve the base metal in ...
3
votes
1answer
239 views

Cyclopentadiene/etc. hydrophobicity after nitrogen atom substitution at a double bond?

If I take a compound like cyclopentadiene ($\ce{C5H6}$) and I substitute a nitrogen for a carbon at one of the $\ce{C=C}$ bonds (making a $\ce{C=N}$ bond), how does this typically change the ...
1
vote
1answer
2k views

Internal and external pressure during a gas expansion

There is a solid substance in a rigid cylinder with a piston placed on top such that the distance between the piston and the bottom of the cylinder is essentially zero, and then the substance ...

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