# All Questions

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### Relation between chemical kinetics and chemical equilibrium

In my chemistry book, the law of chemical equilibrium is derived from the law of mass action: For a reversible chemical reaction $$\ce{aA +bB\rightleftharpoons cC + dD}$$ where $a$, $b$, $c$ and $d$ ...
5k views

### How is it that the equilibrium constant does not depend on the mechanism?

For a reaction of the form $$\ce{aA + bB <=> cC + dD}$$ the equilibrium constant is $$K_c=\frac{[\ce{C}]^c[\ce{D}]^d}{[\ce{A}]^a[\ce{B}]^b}$$ regardless of the mechanism of the reaction. ...
8k views

### Strongest negative inductive effect group between trimethylammonium, ammonium and dimethylsulfonium groups

Which of the following group exerts the strongest -I effect? $\ce{-N(CH3)3+}$ $\ce{-NH3+}$ $\ce{-S(CH3)2+}$ $\ce{-F}$ My idea is that positive species exerts more -I effect than ...
10k views

### How can the Bonding in IF7 be explained using LCAO method?

I know that the VSEPR theory explains $\ce{IF_7}$ (iodine heptafluoride)'s structure as a pentagonal bi-pyramidal one. The valence bond theory can be used to say that it has $\mathrm{sp^3d^3}$ ...
21k views

### Inductive effect and hyperconjugation - one elephant, different parts?

Are the inductive effect and hyperconjugation both different ways of looking at the same phenomenon - i.e. methyl groups donate negative charge for example. Inductively we can argue that carbon is of ...
37k views

### Oxidation state of the sulfur atoms in the thiosulfate Ion

What are the oxidation states of the two inequivalent sulfur atoms of the $\ce{S2O3^{2-}}$ molecule? For all I know is that Lewis Structure does matter in most of the cases.
18k views

### What is active mass?

I'm aware of the fact that active mass is defined as the molarity of a substance, but my textbook states that "Active masses are dimensionless quantities but for our purposes we generally take them ...
36k views

### What do the quantum numbers actually signify?

I know how to calculate them and such stuff, but I wanted to know what they actually signify. I have a vague idea that they have something to do with an electron's position in an atom but what do all ...
135k views

### Why does chlorine have a higher electron affinity than fluorine?

Since fluorine has its valence electrons in the n=2 energy level, and since chlorine has its valence electrons in the n=3 energy level, one would initially expect that an electron rushing towards ...
21k views

### Products of Reimer–Tiemann reaction of 4-methylphenol

p-cresol (4-methylphenol), undergoes the Reimer–Tiemann reaction upon treatment with chloroform ($\ce{CHCl3}$) in alkaline medium. Which of the following is the major and minor product? A. 2-...
5k views

### Number of diastereomer pairs of 1,3-dichloro-1,2,3-triphenylpropane

How can I determine the number of possible pairs of diastereomers here? My first guess was two: RR with RS and SS with RS. But what about the potential chirality center middle carbon? There are two ...
6k views

### How can the gauche-effect be explained?

Generally, anti-conformations are more stable. But in the case of 2-fluoroethanol, the gauche confirmation is more stable. It's given in March's advanced organic chemistry book that intramolecular ...
14k views

### What is the Ka of OH- and Kb of H3O+?

What is the $K_\mathrm{a}$ of $\ce{OH^-}$ and $K_\mathrm{b}$ of $\ce{H_3O^+}$? Have these constants been determined?
15k views

### What is hyperconjugation?

What is hyperconjugation and how do you know if there is hyperconjugation in a compound? Which orbitals are involved in hyperconjugation?
7k views

### Does the shared electron in Covalent bonds revolve around nucleus?

We know that electrons are charges that revolve around the nucleus. Then, when in covalent bonds the electron is shared; does the electron obey the rule?
2k views

### How to assign E/Z configuration according to the Cahn-Ingold-Prelog rules when subsituents differ only by stereochemistry

I stumbled-upon this compound: I'm wondering how to determine the configuration of the double bond. Is it E or Z? How do I decide on the priorities when the substituents can only differ in the ...
2k views

### Why don't trigonal S and P compounds undergo inversion at room temperature?

Most molecules containing nitrogen atoms in trigonal pyramid configuration undergo a relatively fast process of inversion at room temperature. On the other hand, the free energy barrier for phosphines,...
4k views

### Why are solid phase organics often conjugated to HCl?

Many uncharged organic compounds are sold in solid phase with HCl conjugate - e.g. the antihistamine diphenhydramine.HCl or the derivitizing agent pentafluorobenzyl hydroxylamine.HCl, among many ...
3k views

### What makes carbon special and versatile?

My teacher told me that carbon's tetravalency and high catenation ability makes it special and is the reason why there are millions of compounds of carbon. 1) Silicon is tetravalent too but doesn't ...
10k views

### Why does hydrogen bonding in salicylic acid make it more acidic?

When salicylic acid deprotonates (losing the proton from the carboxyl group) it forms a hydrogen bond with between the oxygen in the carboxylate anion and the hydrogen in the alcohol group. However, ...
37k views

### Why do molecules having a higher relative molecular mass have stronger inter-molecular forces?

Why do molecules like alkanes with higher relative molecular mass ($M_\mathrm r$) have stronger intermolecular forces? For example, methane ($\ce{CH4}$) has a weaker intermolecular force than pentane (...
63k views

### What is the definition of organic compounds?

According to the definition of organic compounds on Wikipedia: An organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon. ...
509 views

### What is the meaning of “superionic”?

I see the term "superionic" applied to high pressure water in articles like Giant planets may host superionic water, but I don't understand what the term really means. How is "superionic" ...
45k views

### What is the electronic configuration of Fe(II) ion?

The electronic configuration of Fe is $\ce{[Ar] 3d^6 4s^2}$. So after removing two electrons the configuration becomes: $\ce{[Ar] 3d^6}$ But why can't the electrons rearrange themselves to give a ...
8k views

### How can the equilibrium shift, while Kc remains constant?

Consider the following reversible reaction. $$\ce{Cr2O7^2-(aq) + H2O(l) <=> 2 CrO4^2-(aq) + 2 H+(aq)}$$ What will happen to the position of equilibrium and the value of $K_c$ when more $\ce{H+}$ ...
55k views

### Why doesn't copper react with hydrochloric acid while the other metals do?

5) Which one of the following metals does not react with hydrochloric acid? A. zinc B. magnesium C. iron D. copper E. aluminium The right answer must be copper, but why ...
3k views

### Strong and Weak Acids/Bases

I'm so confused... $\ce{HClO}$ is a weak acid. then why is its conjugate base, $\ce{ClO-}$, a weak base in water? shouldn't they be inversely proportional? shouldn't $\ce{ClO-}$, be a strong base? ...
944 views

### How does the radial distribution function of Vanadium differ from that of Calcium and how does this affect the ionic electron configurations?

When Vanadium is ionised it loses the 4s electron first, meaning that it's 3+ ion has a different electron configuration to Calcium despite it being isoelectronic. Can it be explained in terms of ...
12k views

### Hybridization in PH3

Does $\ce{PH3}$ exhibit $\ce{sp^3}$ hybridization? Arguments against hybridization: $\ce{PH3}$ is less basic than $\ce{NH3}$. This jibes with the supposition that $\ce{PH3}$ keeps its lone pair in ...
11k views

### Why can a face-centered cubic lattice not be redrawn as a body-centered tetragonal lattice?

A base-centered cubic lattice can be redrawn as a primitive tetragonal lattice, therefore we do not include it in the list of Bravais lattices. Why is it then that a face-centered cubic lattice cannot ...
13k views

### Can ozone have a triangular structure?

The structure of ozone is traditionally depicted using two resonance forms: However, what I am wondering is instead of using such an idea to explain the structure why can't we show the structure of ...
Doing a first year chem class. Just read through the molecular naming of compounds and now I'm confused as to why $\ce{CaCl2}$ is called calcium chloride and not calcium dichloride?