Greg E.
  • Member for 9 years, 7 months
  • Last seen more than 6 years ago
  • Michigan
Nitration of Aromatic Compounds
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It's not advisable to consider these types of reaction schemes in a slavishly literal fashion. In reality, there are multiple proton transfer equilibria occurring simultaneously, and the reactions ...

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E2 Elimination; Anti-periplanar beta hydrogen
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If the elimination occurs via an ${\mathrm{E_2}}$ mechanism, the other endocyclic double bond (i.e., the one between the two methyl bearing carbons) cannot be formed, as the $\ce{C_2}$ $\beta$-...

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Any possible additives to a drain cleaner I use as a source of NaOH?
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The product you've described contains the following ingredients (per the ingredient data sheet on the manufacturing company website): Sodium hydroxide Sodium chloride Aluminium Mineral oil One ...

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Lewis Structures - Peripheral Octets
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Quoting Greenwood & Earnshaw's Chemistry of the Elements, discussing the triatomic polyhalide anions: [I]nteratomic distances [...] are individually always substantially greater than for the ...

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Why does fusing benzene rings not produce polycyclic alkynes?
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The ideal bond angles for alkynes are $180^{\circ}$, which is necessary for optimal overlap of atomic orbitals combining to produce mutually perpendicular $\pi$-type molecular orbitals. Any ...

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What salts (or other substances) are available for increasing water's boiling point?
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For relatively dilute solutions of non-volatile solutes, the following equation (which assumes ideal behavior) can be used to predict boiling point elevation with reasonable accuracy: $$\Delta T_b = ...

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How does neutralization of free radicals by $\beta$-carotene work?
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The extended, conjugated series of alternating double-bonds in $\beta$-carotene comprises a system of highly delocalized $\pi$ electrons. If a radical forms by hydrogen abstraction at one of the two ...

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Can redox reactions involve only non metals?
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A redox reaction is one in which oxidation state of some atom changes, and such reactions need not involve metals, nor any ionic species. Oxidation state is the idealized charge that a given atom ...

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Is carbon dioxide more acidic than carbon monoxide?
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Carbon dioxide is a much stronger Lewis acid than carbon monoxide. In carbon dioxide, the carbon has a much higher oxidation state (formally, $+4$ vs. the $+2$ of carbon monoxide), and the two oxygen ...

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Which is better leaving group
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I presume you're referring to $\ce{Br-}$ and $\ce{Cl-}$ in aromatic nucleophilic substitution reactions. In that case, $\ce{Br-}$ is typically the superior leaving group to $\ce{Cl-}$, due to the ...

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index of hydrogen deficiency
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You seem to be using a very simplified version of the index of hydrogen deficiency. A more complete expression is: $$IHD = \frac{2C + 2 - H - X + N}{2}$$ Where $C$, $H$, $X$, and $N$ represent the ...

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Azeotropes and separation by distillation?
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You seem to have the right idea. To elaborate, take the specific example of the positive azeotrope of (roughly) 96% ethanol and 4% water. If you begin with a mixture containing less than 96% ethanol, ...

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Which compound reacts most slowly?
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Electrophilic aromatic substitution, of which nitration is one specific example, is often a kinetically controlled process, i.e., the distribution of products is determined by the energies of the ...

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In Goodman and Gilman what does R,S-citalopram refer to?
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It seems fairly clear that the authors intended to refer to the racemic mixture there. You're right that a comma would normally be used to separate the locants of distinct stereocenters when multiple ...

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When is it okay to use $Q=mc\Delta T$, is this equation only for calorimetry questions?
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The equation $Q = mc \Delta T$ is appropriate for calorimetry at a constant volume. $Q$ here refers to the net heat transfer of the isolated system. Change in enthalpy, $\Delta H$, on the other hand, ...

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Why are elements on the right side of the periodic table nonmetallic and gas at room temperature?
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The elements on the left-side of the periodic table are relatively electron deficient (i.e., they have few valence electrons), and due to their comparatively low effective nuclear charges (the net ...

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How much CO₂ should one expect in an IR spectrum?
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From what I've read (and personal experience with IRs I've run), a relatively intense $\ce{CO2}$ asymmetric bond stretching signal at approximately $\ce{2350cm^{-1}}$ is an extremely common background ...

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Reaction Pathways - Substitution and elimination
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In theory, one can substitute a leaving group with retention of stereochemistry by performing two successive $\mathrm{S_N2}$ reactions. The first one inverts stereochemistry, and the second one ...

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What are the priorities for substituent groups on a cyclohexane?
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If the numerical sequence of locants is equivalent, the numbering should be assigned to correspond with alphabetical order. Hence, in your example, correct would be 1-ethyl-2-methylcyclohexane. ...

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Atmopsheric Gas IR-Spectra
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Completely symmetrical diatomic molecules like $\ce{O2}$ and $\ce{N2}$ are not IR-active because they have a zero dipole moment, even when oscillating within their one vibrational mode. Hence, there ...

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Basic chemistry of the Shinoda test for flavonoids?
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I found one source indicating that the reaction involves the conversion of the flavonoid to the corresponding anthocyanidin. The structure of that resulting anthocyanidin contains an extended system ...

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When will peroxide form?
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From Greenwood and Earnshaw's excellent book Chemistry of the Elements: When the metals are burned in a free supply of air the predominant product depends on the mtal: $\ce{Li}$ forms the oxide $\...

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Balanced equation for synthesis of p-nitrophenol from p-nitrodiaznoium chloride salt and sulfuric acid/water?
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The water is the source of the hydroxyl ($\ce{-OH}$) group in the phenol, which accounts for one oxygen and one hydrogen. The other hydrogen is ultimately abstracted, probably by a second molecule of ...

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Oxidizing 2-Methylpropan-2-ol using potassium dichromate. Why is heating required?
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Tertiary alcohols (such as 2-methyl-2-propanol, in your specific case) cannot be directly oxidized by $\ce{Cr(VI)}$ salts like $\ce{K2Cr2O7}$ because they have no $\alpha$-hydrogen. On the other hand, ...

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Constitutional isomers of cis-1,2-dibromocyclopentane
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If I understood you correctly, your objection is to the relative cis- designation in the name of the compound. As far as I can tell, the use of any stereochemical designation within the context of ...

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Nomenclature for stereoisomer example possible wrong?
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Unless I'm very much mistaken, this molecule should not be labelled with any stereochemical descriptors, whether they be relative (cis/trans) or absolute (E/Z). The double bond has three identical ...

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Does a sulfuric acid/nitric acid mixture dissolve PTFE (ie. teflon)?
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I can't claim to have any personal experience with that sulfuric acid/nitric acid cleaning mixture specifically, but, as far as I'm aware, PTFE is generally inert towards acids. As a testament to that,...

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When should we not draw a Lewis dot structure?
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Short answer: no, there's nothing preventing you from drawing arbitrarily complex molecules according to the conventions of Lewis dot structures. They are not special, and the rules for drawing them ...

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How can silver work as a disinfectant in a bathtub if precipitates in the presence of chloride?
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If you're referring to chlorination of public water supplies, keep in mind that this is likely not the main source of chloride ion. Elemental chlorine disproportionates via the following reaction: $\...

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Identifying Reaction Types
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It's true that a precipitation reaction will always yield at least one solid product, but not every reaction that yields a solid is, strictly speaking, properly categorized as a precipitation reaction....

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