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2 votes
1 answer
170 views

How to name LiN(CF2SO3)2?

I found this compound in the list of inorganic lithium salts from this article on ScienceDirect. It is said to be of the sulfonate group. Let's focus on the anion alone. I'm not sure if it can be bis(...
Blacklight MG's user avatar
4 votes
1 answer
434 views

Why is pyramidal structure observed in trisilylphosphine?

Why does trisilylphosphine $\ce{P(SiH3)3}$ (ICSD Entry: 72676, [1]) have a pyramidal structure while trisilylamine $\ce{N(SiH3)3}$ (ICSD Entry: 201428, [2]) is planar? I think since silicon has a ...
Substitute_Y's user avatar
4 votes
1 answer
2k views

Which is really water soluble, amylose or amylopectin?

In my textbook it was written that amylose is more water soluble than amylopectin. But as I searched for the reason I found a totally opposite information. https://pubs.acs.org/doi/pdf/10.1021/...
satoru kurita's user avatar
4 votes
3 answers
1k views

Does manganese reacts with water at "not" standard conditions?

In my answer, I stated that manganese is said to not react with water under normal conditions although some sources say it reacts with water to liberate hydrogen gas. Does it implies that it reacts ...
Nilay Ghosh's user avatar
  • 26.8k
3 votes
0 answers
108 views

Does solid manganese reacts with atmospheric air when heated?

As discussed in my answer, manganese is not particularly reactive to air. The surface of manganese lumps oxidize to a minor extent but when it is finely divided, it becomes pyrophoric and burns in air....
Nilay Ghosh's user avatar
  • 26.8k
0 votes
1 answer
98 views

Determining the average relative mass of an element from the percentage of isotopes

Suppose we have an element $\ce{A}$. Its relative mass is $16$ and it has three isotopes: $\ce{^16A}$ ,$\ce{^17A}$ and $\ce{^18A}$. The available percentage of $\ce{^17A}$ is $0.037\,\%$. What is the ...
Sayem Rahman's user avatar
3 votes
2 answers
340 views

Reaction between sodium hydroxide and phosphorus trioxide

My chemistry textbook [1], chapter Periodic Properties of Elements, section p-Block elements — formation of oxides suggests that the reaction is $$\ce{P2O3 + 2 NaOH -> 2 NaHPO3},\tag{R1}$$ but ...
Nazmul Hasan Shipon's user avatar
7 votes
1 answer
176 views

Is there an error at page 138, 4.4 of Introduction of Computational Chemistry 3rd Edition?

Firstly, I found the RHF expansion of $\Phi_2$ and $\Phi_3$ is not symmetric at equation (4.29). Then I expand $\Phi_2$ by myself, the results showed it's $ \Phi_2 = (\chi_A\chi_A-\chi_B\chi_B)(\alpha\...
M. Chen's user avatar
  • 181
1 vote
1 answer
5k views

Radius ratio of octahedral interstitial site in BCC lithium

Problem Determine the minimum radius of an atom that will just fit into (a) the tetrahedral interstitial site in FCC nickel and (b) the octahedral interstitial site in BCC lithium. Solution (a) For ...
AfiJaabb's user avatar
  • 284
3 votes
2 answers
2k views

Mesomeric effect in -NHCOR and -OR

I've read in Wikipedia about +M strength of groups which goes: –O - > –NH2 > –NHCOR > –OR > –OCOR > –Ph > –CH3 > –F > –Cl > –Br > –I Now in every other website states ...
Neha's user avatar
  • 462
5 votes
1 answer
424 views

Mechanism for Diels–Alder of alkene with substituted thiophene sulfone with loss of sulfur dioxide

I came across a synthesis of centrohexaindane that has the following steps: This is a Diels–Alder reaction that gives an aromatic ring. I know that alkynes will give this reaction as follows: But in ...
bud's user avatar
  • 460
2 votes
0 answers
204 views

Are (1R,2S)‐1,2‐dibromocyclopentane and (1R,3S)‐1,3‐dibromocyclopentane positional isomers?

Are these positional isomers or not? According to me they are, since Br substituent is located at different positions in both the pictures, but the answer key in one of my mock test websites says they'...
Aashita's user avatar
  • 71
2 votes
2 answers
438 views

Why is degree of dissociation used to estimate strength of an acid?

Problem Which of the following will give strength of acid? A) pH B) Normality C) Degree of dissociation D) Dissociation constant Answer Question If pH is not considered as a metric to assess the ...
Ashish's user avatar
  • 1,419
0 votes
1 answer
705 views

Calculating atomic mass of unknown element in given compound (gas) at STP

A gas $\ce{X2O5}$ has the density of $\pu{5 g L-1}$ at STP. What is the atomic mass of $\ce{X}$ given $A_\mathrm{r}(\ce{O}) = 16?$ Note: The problem is my homework for school and has been translated ...
Gaurav Mall's user avatar
9 votes
2 answers
1k views

Orientation of external cell when voltage is supplied by it to voltaic cell so as to oppose its cell potential

Given below is a page from our Chemistry Textbook: As it can be seen, the direction of $E_{ext}$ in figure $3.2(c)$ is opposite to the direction in figures $3.2(a)$ and $3.2(b)$. I understand that $...
Alpha Delta's user avatar
5 votes
0 answers
114 views

Is there a mistake in diagramatic representation of RS perturbation theory described in Szabo and Ostlund textbook?

I'm trying to understand rules of the diagrammatic representation of the many body perturbation theory that described in Szabo and Ostlund "Modern Quantum Chemistry" textbook. One of the ...
Nikolay's user avatar
  • 51
4 votes
1 answer
1k views

MolView is unable to generate correct 3D structure for hydroxypropadiene

MolView is unable to generate the correct structure of hydroxypropadiene. It instead generates the structure of acrolein (which has the same molecular formula). Why is this so? Is it because ...
Aniruddha Deb's user avatar
7 votes
1 answer
930 views

Boiling point of oxygen

I am studying chemistry from the book titled "Fundamental Chemistry for Cambridge O Level" written by Rosemarie Gallagher and Paul Ingram. On page 17, it states that oxygen boils at −219 °C and ...
user avatar
1 vote
2 answers
1k views

How can iodine oxidise hydrogen peroxide?

The following is mentioned in NCERT (government textbook in India used in all schools) under chemical properties of $\ce{H2O2}:$ (iv) Reducing action in basic medium $$\ce{I2 + H2O2 + 2 OH- -> 2 I-...
Harsh jain's user avatar
  • 1,723
0 votes
1 answer
112 views

Does it sometimes take energy to create a chemical bond? [duplicate]

Wikipedia says so: Bonds can also be broken apart. Since most bonds require energy to form, they also give off energy when they are broken. But before most bonds break, the molecule has to be ...
harjinder singh sardar's user avatar
2 votes
1 answer
486 views

Barron states that 4.18×10⁸ joules equal 1 kcal, is this correct?

Here is a paragraph in Barron's SAT chemistry prep book: Work itself is measured in Joules, and so is energy. In some problems, however, energy may be expressed in kilocalories. The relationship ...
Luke Kong's user avatar
-1 votes
1 answer
267 views

Is there a error at page 566 of Atkins Physical Chemistry? [closed]

At page 556 I found this question being analyzed and the rate law is provided. However, when I apply steady state approximation, I can't find the result without the factor 2. Is it me being wrong?
David Li's user avatar
2 votes
1 answer
436 views

Possible erratum in solutions to Orbital Interactions in Chemistry 2ed [closed]

I was attempting the problems in Chapter 1 of Orbital Interactions in Chemistry, and found a slight problem. ftp://ftp.wiley.com/public/sci_tech_med/orbital_interactions_2e/Chapter%201%20-%20Answers....
ANZGC FlyingFalcon's user avatar
0 votes
0 answers
623 views

Is it possible to obtain n-butane by treating halopropane grignard reagent with methanol?

The answer is a,b. My mechanism however doesn't give n-butane when R is propyl. Is this a case of textbook errata? Himanshu Pandey, Advanced Problems In Organic Chemistry, 9th edition ...
Avyansh Katiyar's user avatar
0 votes
0 answers
171 views

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
Avyansh Katiyar's user avatar
2 votes
0 answers
269 views

What is the product of the following series of reactions?

. The answer given to this question is . This is how I attempted solving the problem. Considering that my answer and the author's answer is differing only by a methyl group, is this a publishing ...
Avyansh Katiyar's user avatar
2 votes
0 answers
442 views

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, $j$ ...
Martin's user avatar
  • 749
3 votes
1 answer
153 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 ...
user61822's user avatar
  • 253
0 votes
1 answer
131 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=(\...
Maxwell's Ghost's user avatar
1 vote
0 answers
57 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 ...
RTStriker's user avatar
2 votes
1 answer
3k 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, ...
Arjun Puri's user avatar
5 votes
0 answers
161 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 ...
Gale Staneva's user avatar
4 votes
2 answers
3k 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?
Dante's user avatar
  • 185
0 votes
0 answers
300 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-...
George Tian's user avatar
  • 1,381
0 votes
0 answers
114 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 ...
phi2k's user avatar
  • 1,469
0 votes
1 answer
288 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 ...
Gaurang Tandon's user avatar
2 votes
2 answers
1k 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 ...
Selena's user avatar
  • 399
6 votes
1 answer
2k 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: ...
Tan Yong Boon's user avatar
3 votes
1 answer
127 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 ...
Pranav Ballaney's user avatar
5 votes
1 answer
5k 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 "...
paracetamol's user avatar
  • 18.8k
2 votes
1 answer
2k 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 ...
paracetamol's user avatar
  • 18.8k
10 votes
1 answer
21k 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?
zzzlkj's user avatar
  • 111
1 vote
1 answer
824 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 ...
Asmaa's user avatar
  • 153
9 votes
2 answers
8k 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 ...
paracetamol's user avatar
  • 18.8k
4 votes
1 answer
810 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 because it is ...
Anon's user avatar
  • 51
0 votes
1 answer
607 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 ...
user53300's user avatar
3 votes
1 answer
10k views

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 (...
paracetamol's user avatar
  • 18.8k
1 vote
0 answers
726 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{...
Saadman Yasar's user avatar
0 votes
0 answers
849 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 ...
chail10's user avatar
  • 688
4 votes
1 answer
1k 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", ...
Gaurang Tandon's user avatar