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Questions tagged [erratum]

For questions that deal with possible errors in a specific statement of a specified book, article, website, etc. These questions should always include a complete reference (see tag wiki for format).

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Attack of 3-methylbutan-1-ol on benzene in acidic medium

That's how I proceeded with the question. However the answer is tert-butylbenzene. I can't figure out why do I have an extra carbon atom. SOURCE - JEE Advanced 1994
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What will be the product of the following series of reactions

. The answer given to this question is . This is how I attempted the problem. Considering that my answer and the author's answer is missing only a methyl group, is this a publishing error or am ...
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Pressure in Skoog Instrumental Analysis Problem 27-22b (gas chromatography)

Problem 27-22b in: Skoog; Holler; Crouch. Principles of Instrumental Analysis. Thomson Brooks/Cole (publisher varies by country) asks for corrected retention volumes. A compressibility factor, $j$ ...
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1answer
124 views

Is there a case when an atom of some element (e.g. carbon) does not have its expected number of protons (e.g. 6)?

Page 12 of the Study Guide for Campbell Biology, 11th Edition has the following question: A carbon atom has 6 neutrons. How many protons are present in the nucleus of a carbon atom? A. 12 ...
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1answer
66 views

thermochemistry problem confusion

I can understand upto where the ideal gas equation is used to calculate volume of steam. But on trying to find out $ \Delta V$ , i saw that there are no gases on the reactant side so then $P\Delta V=(\...
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42 views

Find the Electronic Configuration of an Iron Atom [closed]

I'm confused. Iron has 26 electrons and I wrote down $\ce{1s^2, 2s^2, 2p^6, 3s^2, 3p^6, 4s^2, 3d^6}$ yet my answer booklet says $\ce{1s^2, 2s^2, 2p^6, 3s^2, 3p^6}$ but that is only 18. How can it be ...
2
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1answer
301 views

Classification of the Inside of a Grapefruit

In the text Chemistry: The Central Science, the inside of a grapefruit is classified as a homogeneous mixture. Unless I’m missing something, to me it would be a heterogenous mixture owing to pulp, ...
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0answers
79 views

Why is the carbon atom omitted from the molecular formula?

In my chemistry textbook, the following reaction was given: I have two questions related to the marked in orange boxes/parts of the image: Why is the molecule symbolized by $\ce{(CH3)3Cl}$ instead ...
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2answers
151 views

What is the expected product in the reaction of hydrogen chloride with allylbenzene?

Shouldn't it be 4th option since since the carbon attached to the ring is secondary as well as resonance stabilized?
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80 views

Steric hindrance during Hydroboration

In response to this diagram (Organic Chemistry By David Klein 3rd Edition Page 364): The textbook stated A comparison of the transition states for hydroboration via Markovnikov addition or anti-...
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0answers
85 views

Does S use its p-orbitals for bonding? [duplicate]

This question was inspired from the following questioN: I thought the answer would be either A (maybe accounting for larger sizes?) or B (Bent's rule) but apparently the answer is D. Can someone ...
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1answer
71 views

Same set of carboxylate reagents yielding two different products with an alkylide

I recently came across two contrasting products for the same set of reagents - carboxylic acid and alkyllithium, and wish to understand why exactly any difference exists between the two. Reaction 1 ...
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2answers
986 views

How can the outermost electrons in silicon be 2s and 2p electrons?

My book says the number of outermost electrons in silicon is $4$. Yes, right. But then it says those are $\ce{2s}$ and $\ce{2p}$ electrons. The electronic configuration of silicon is $\ce{1s^2 2s^2 ...
5
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1answer
314 views

Why are 3 equivalents of organolithium needed in synthesis of ketone from carboxylic acid?

For the reaction of a carboxylic acid and organolithium reagents to synthesise a ketone, Clayden's, on p 219, mentions: Notice that three equivalents of organolithium are needed in this reaction: ...
2
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1answer
60 views

How can a methyl halide react by intramolecular SN2?

Out of the following, $\ce{CH3Br}$ doesn't react by which mechanism? SN2 SN1 E2 Intramolecular SN2 E1 My textbook gives 2, 3 and 5 as the correct answers, which means it does react ...
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0answers
625 views

Is it a “Bary center” or a “Bari center”?

(Studying Coordination Chemistry, "Crystal Field Theory" at school) Apparently, different sources spell this differently. The Wikipedia article on Crystal Field Stabilization Energy, calls it the "...
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1answer
220 views

“Nitrogen (gas) is physisorbed over iron (metal) at room temperature”: Is this for real? [closed]

My copy (PDF) of Levine's Physical Chemistry (6th ed.), page 570-571, section: "Adsorption of Gases on Solids", states: Physical adsorption is nonspecific. For example, $\ce{N2}$ will be physically ...
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1answer
3k views

Are all ionic compounds salts?

According to Wikipedia: A salt is an ionic compound that can be formed by the neutralization reaction of an acid and a base. Are all ionic compounds salts? Are all salts ionic compounds?
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1answer
34 views

Where does the additional hydrogen in the Fischer depictions of glucopyranose come from?

My book shows this figure of Fischer formula of D-glucose: I don't understand this figure, and I wonder why the upper carbon atoms in both the right and left formulas have 5 bonds. And from where ...
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1k views

Why can't I dry/concentrate ethanol using calcium chloride … or can I?

My (very unreliable) school textbook tells me: Lower alcohols form a solid derivative with certain metal salts. and, It is for this reason that ethanol cannot be dried/concentrated using ...
4
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1answer
216 views

Can a bond be electrophilic or nucleophilic?

The indicated bond is: A) Nucleophilic because it is electron-deficient. B) Electrophilic because it is electron-rich. C) Nucleophilic because it is electron-rich. D) Electrophilic ...
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1answer
164 views

Chemical Kinetics / Rate Question — Error in Textbook Question/Answer?

I am reading Kaplan's General Chemistry MCAT Review 2018-2019, and think that one of its chemical kinetic questions is wrong. (Or perhaps I am simply missing something). I have attached an image of ...
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1answer
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The “Ostwald Isolation Method”: How does this work?

Recently started reading up on Chemical Kinetics, and I came across a certain "Ostwald Isolation Method" that figures in my school-issued workbook. Apparently, it's used to determine (approximately) ...
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0answers
429 views

Does the rate of dissociation of PCl5 increase in presence of Cl2

I'm sorry if this is somehow inappropriate to ask but I've found a rather strange question on my text book that asks "Why does the rate of dissociation of $\ce{PCl5}$ increase in the presence of $\ce{...
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0answers
162 views

Is a SR2+ substituent really more electron-withdrawing than NH3+?

As the electronegativity of nitrogen and sulfur are around 3.04 and 2.58, respectively (according to the Pauling scale). So according to that, $\ce{NH3+}$ should pull the electrons more towards it ...
5
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1answer
256 views

What exactly does the “per mole” unit of heat of atomization mean?

I am facing a confusion in the definition of the standard enthalpy of atomization. The confusion arises because of the "per mole" in its units ($\pu{kJ mol^-1}$). My question: When I say "per mole", ...
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0answers
247 views

Can final volume differ from initial volume in a constant volume process?

A sample of 1.00 mol perfect gas molecules with $C_{p,\mathrm m} = 7R/2$ is put through the following cycle: (a) constant-volume heating to twice its initial volume, ... (Problem 2.5, Atkins Physical ...
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2answers
6k views

Does fumaric acid form stronger hydrogen bonds than maleic acid?

My book claims: Fumaric acid can form intermolecular hydrogen bonds (strong) while maleic acid forms intramolecular hydrogen bonds (weak), hence fumaric acid has higher boiling point than maleic ...
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1answer
123 views

Can a first degree carbocation form if a methyl shift is possible?

I was going through a reference book when I stumbled upon this question Is that even possible?
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1answer
103 views

Enantioexcess for a non-chiral molecule?

I am trying to understand this quote in a section on "Biotransformations of Organic Molecules" from a handbook I am reading: [...] Euglena gracilis could convert acetophenone to 2-phenylethanol; ...
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2answers
2k views

Configuration of chiral center in cocaine

I couldn't get the absolute configuration for the chiral center I marked. I got R, but according to my answer key it is apparently S. Would really appreciate an explanation.
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1answer
192 views

Bohr Radius Confusion

I saw online that the radius for each level is defined by the formula: $$r_n=n^2 r_1$$ Where $r_1$ is approximately $53\ \mathrm{pm}$. However, on the Barron's AP chemistry book 7th edition, it ...
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1answer
1k views

Can a table salt + vinegar mixture be explosive?

I remember having read in a book, Ask Me Anything (Dorling Kindersley), that a combination of copious amounts of table salt and vinegar is explosive. Now this was a really long while back, and I can'...
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2answers
2k views

What happens when prop-2-en-1-ol reacts with concentrated hydrogen bromide

What happens when prop-2-en-1-ol (allyl alcohol) reacts with concentrated hydrogen bromide? My Idea: I thought that in the first step protonation of the hydroxyl group will take place followed by ...
3
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0answers
430 views

Problems with Daniell cell

In Zemansky and Dittman's book on thermodynamics, pages 41–43, the authors discuss the Daniell cell as a thermodynamic system. Their cell consists of two saturated $\ce{CuSO4}$ and $\ce{ZnSO4}$ ...
2
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1answer
335 views

Beryl is a mineral which contains 5.03% Be, 10.4% Al, 35.5% Si and 53.58% O. What is the simplest formula for beryl?

So I tried to follow a 3 step rule to solving this equation: Divide each % by it's own atomic mass Dived each of those by whichever is smallest Find the lowest whole # Be = 5.03% / 9 = .558 ...
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2answers
1k views

What exactly does κ stand for in this equation connecting solubility and molar conductivity?

I came across the following equation while studying electrochemistry ("Physical Chemistry" by Wallwork and Grant): The solubility $s$ of a sparingly soluble salt can be determined from conductivity ...
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2answers
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Correct equation for Ionic Conductivity (λ) in Solutions?

We haven't started on Electrochemistry at school yet, but I did manage to find some time to read up on the topic. One thing I've noticed from when I started, is that different books and sites use ...
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2answers
8k views

What is the difference between molar conductance and molar conductivity?

I'm learning (or at least trying to learn) about electrochemistry, but a major obstacle to that, is that different books I refer use different terms for the same symbols. So in a last ditch attempt to ...
5
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1answer
322 views

Is Nitroglycerine a Nitro Compound or an Ester?

I looked up nitroglycerine in a science dictionary (Oxford Dictionary of Science, 2003), and it explicitly mentions that nitroglycerine is an ester and not a nitro compound. However my teacher told ...
3
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0answers
57 views

Spectrochemical Series - Latest version?

--Studying the Crystal Field Theory [under Coordination Chem.] at school now-- A book my teacher lent me [printed in 2002] has the spectrochemical series in it, and it depicts pyridine [py] as having ...
3
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1answer
2k views

Why is the solubility of sodium acetate trihydrate so much lower than anhydrous sodium acetate?

According to Wikipedia: Solubility of anhydrous sodium acetate in water at 0 $^{\circ}$C is 119 g/100 mL (AKA 1.495 mol/100mL) Solubility of trihydrate sodium acetate in water at 0 $^{\circ}$C is 36....
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1answer
208 views

Clarification about Frost diagram y-axis conventions?

I was looking at the Frost diagram of Manganese, and on the UC Davis ChemWiki, I see this one: However, the one straight from my textbook, "Descriptive Inorganic Chemistry" (Overton), looks like this:...
3
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1answer
2k views

Does the addition of water to N2H4 produce N2H4

I am currently calculating the $\ce{pH}$ of a species. The reaction is as follows, $$\ce{N2H4 + H2O <=> N2H_{$A$}+ + OH-}$$ However, I'm not sure what the value of $A$ will be. In my ...
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1answer
405 views

Is these a pair of diastereomer or identical compound?

I attempted on this question (e) and found out that they are diastereomers, but the answer from the book is that they are identical. I worked out the configuration at each of the centres for the ...
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3answers
8k views

kJ per mole or kJ per 2 moles?

From Chemguide: Is the measurement unit $\ce{kJ*mol^{-1}}$ correct here? Shouldn't it be measured simply in kJ, because the $-572$ figure is for the whole reaction, i.e. for 2 moles of the product?
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2answers
344 views

Error in formula for the solution to a chemical problem

The problem in my textbook goes like this: Burning $0.68\ \mathrm{g}$ of an unknown substance, we obtained $1.28\ \mathrm{g}$ of sulfur oxide (IV) and $0.36\ \mathrm{g}$ of water. Find the chemical ...
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1answer
29k views

How to identify a redox reaction?

Which balanced equation represents a redox reaction? \begin{align} &\mathrm{A.} &\ce{AgNO3 + NaCl &-> AgCl + NaNO3} \\ &\mathrm{B.} &\ce{BaCl2 + K2CO3 &-> BaCO3 + 2KCl} ...
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2answers
2k views

How many significant numbers(figures) are in repeating decimal (105-32)×5/9=40.5555…? [closed]

Source: Basic Chemistry, Steven S. Zumdahl, Donald J. DeCoste Referring to the above, rule it seems $(105-32)\times\frac{5}{9}=40.5555\ldots$ has infinitely many significant figures. Am I correct?
4
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2answers
409 views

Factors affecting mass of a gas-evolving reaction mixture over time

Excess magnesium was added to a beaker of aqueous hydrochloric acid on a balance. A graph of the mass of the beaker and contents was plotted against time (line 1). What change in the experiment ...