All Questions

5
votes
2answers
40 views

Intuition for why catalyst affects both forward and reverse reactions equally?

I have looked for quite a long time on the site however all the answers involve mathematical explanations involving Arrhenius's equation. I would really like an intuitive reason (or one using ...
3
votes
1answer
58 views

What chemical regularly transported by road in the UK would cause serious injury/loss of life if it escaped in a road accident?

I'm writing a story where a serious multi-vehicle pileup happens in the winter during foggy weather. I need the fallout from this to include the escape of a substance that will cause significant ...
1
vote
0answers
7 views

Can any body Suggest me a set up that I can build it up to study the surface roughness of transparent polymeric fibres?

I need to study the surface of nylon-6 blank fibres with a thickness of nearly 40 micrometre, I work in optics lab with many optical components such as beam splitters, lenses, mirrors ... etc, can I ...
-2
votes
0answers
28 views

Gaussian syntax error on the input line

I ran a Gold complex in Gaussian 09 with the following exact Route Section PBE0/LANL2DZ Opt Freq NoSymm and it gave me this error message: ...
4
votes
0answers
21 views

Optimized General Contractions using the EMSL Basis Set Exchange

When using the EMSL BSE Database and selecting a basis set, one can choose the "Optimized General Contractions" or not. When doing so for, e.g., Nitrogen and the cc-pVDZ some basis functions are not ...
0
votes
0answers
24 views

Formaldehydes fehlings test

I have read answer to the question, why benzaldehyde and pivalaldehydes do not give fehlings test. But based on those similar lines here in HCHO also we don't have alpha hydrogens,then how will that ...
-1
votes
0answers
10 views

Please tell how to find the final volume with composition [on hold]

Please tell be how to solve the problem because I am unable to find the final volume
-1
votes
0answers
26 views

Which of these species can act as a Lewis acid? [on hold]

$\ce{Fe^{3+}}$ $\ce{CN-}$ $\ce{CH3COOH}$ Would it just be three since it is able to donate hydrogen?
1
vote
0answers
64 views

Predicting the products obtained after addition of bromine and then elimination using alcoholic KOH

If we have an alkene reacting with bromine, then I know that the the reaction happens by a cyclic intermediate. But if we add alcoholic KOH to the products formed, then what will be the major products ...
-2
votes
0answers
30 views

Sulphur monochloride and selenium

Wondering if adding Selenium powder to Sulphur Monochloride results in Selenium monochloride. Anyone?
0
votes
0answers
8 views

Method to determine the maximum coordination number that can be exhibited by any element

I have read that coordination number depends on size,charge ,and electronic configuration . could anyone explain giving a example how to determine the maximum coordination of any element
1
vote
1answer
22 views

Is there any book or text where ionic radius of elements are given?

So my research has me looking for ionic radius characterization. If anyone could post any link or give the name of any book where ionic radius of all elements are given that would be really great?
-2
votes
2answers
82 views

Which molecule is the most acidic? [on hold]

Wouldn't the most acidic be the H connected to F? However, my professor says it is answer A, the alpha Hydrogen in carboxylic acid. Edit: Sorry, I did not phrase my question right. What I meant to ...
0
votes
0answers
14 views

Saponification side reactions

When soap is made from triglycerides and NaOH reacting, is saponification the only reaction that occurs or are there other side reactions. Information concerning this issue seems slim online
-4
votes
0answers
15 views

Affect of pH on temperature [on hold]

It’s common knowledge that temperature has an affect on ph. can ph changes affect temperature? Looking at the human body and the relationship of temperature and ph, it seems like temp. is the ...
-3
votes
0answers
19 views

If that amount, from problem 7, fills a room 500,000 L, then how many parts per million carbon dioxide are in the room? 1 mol of gas occupies 22.4L​ [on hold]

If that amount, from problem 7 (the amount is the propane balanced equation: C3H8 + 5O2 = 3CO2 + 4H2O), fills a room 500,000 L, then how many parts per million carbon dioxide are in the room? 1 mol of ...
-2
votes
1answer
41 views

Is 99% Isopropyl Alcohol sold in stores really 99%?

My understanding is that an azeotropic mixture of isopropanol and water is 91%. This makes sense as to why there are so many brands of rubbing alcohol sold at 91%. There are also some sold as 99%, ...
-1
votes
0answers
25 views

The radial part of the wavefunction squared gives the probability of finding the electron at radius r from the nuclear centre per unit volume [on hold]

'Ψ(r)2' gives the probability of finding the electron at radius r from the nuclear centre per unit volume.' The 'per unit volume' part of the definition is confusing as the definition says 'at radius ...
4
votes
0answers
32 views

Gap in ionic radii

The above picture was shown in a presentation by my prof in inorganic chem as we were discussing ionic radii more in depth (all in pm). These are all isoelectronic radii. Notice the sudden leap in ...
-1
votes
0answers
40 views

The acid HA is 4.1 % hydrolyzed in solution. If the concentration of HA in solution is 2.0 M, what is the pH? [on hold]

The acid HA is 4.1 hydrolyzed in solution. If the concentration of HA in solution is 2.0 M, what is the pH? a. -.91 b. -.30 c. .30 d. .91 g. 2.77 For this problem i have no idea where to go.. ...
-1
votes
0answers
24 views

Butadiene for yoga mats [on hold]

I am researching new ways to make a better yoga mat.Can Butadiene be used in production of Yoga mat? Can Butadiene be infused with essential oils? Thank you
5
votes
1answer
20 views

Help with missing output from cubegen utility after density calculation in Gaussian16

I am busy trying to do density calculations in Gaussian16 as I need the .cube output for input to the PIXEL software. But my Gaussian output seems to be missing an entire chunk of data and I don't ...
1
vote
1answer
40 views

Why does monoammonium phosphate (MAP) have 52% of phosphorus (P₂O₅)?

The formula of monoammonium phosphate (MAP) is $\ce{NH4H2PO4}$. Manufacturers say that MAP has 10% of nitrogen (N) and 52% of phosphorus (P). However, its molecular mass is 115 u and the atomic mass ...
2
votes
0answers
26 views

Where can I look for a short chain photopolymer?

I am by no means an expert in this field, so please be patient with my explanation. I am looking for a photopolymer with very specific properties. I am not sure how realistic it is to find such a ...
0
votes
1answer
31 views

What is the platinum doing in a Zippo hand warmer?

My Zippo hand warmer requires lighter fluid, platinum catalytic burner, and a heat source to start the flameless catalytic process. What is the platinum doing in this reaction?
0
votes
0answers
49 views

MacGyvering medieval poison [on hold]

Anyone know of any compound/substance one could have access to in a stone prison cell (From food? The rocks? The metal bars?) that could be processed through rudimentary means into a quick acting ...
0
votes
1answer
36 views

Buffer Systems, K(NH2)2 and HCL [on hold]

25 .00ml of 0.100M R(NH2)2 with $Kb1=1*10^{-4}; Kb2 = 1*10^{-7}$ is mixed with amounts of .100M HCL a.) 0 ml b.) 5ml c.)10ml d.)12.5ml e.)25.00ml f.)37.50ml g.)50.00ml h.)60.00ml What is ...
0
votes
0answers
21 views

How does chelation control result in rate acceleration?

In the chapter on diastereoselectivity in Clayden, Warren & Greeves (2012), the Cram-Chelate model is discussed. Most significantly, under chelation control, the diastereoselectivity of the ...
0
votes
1answer
40 views

Why aren't all bond lengths equal in cyclobutadiene? [on hold]

even when there is a possibility of conjugation why aren't bond lengths equal?
0
votes
1answer
22 views

Conflicting info on TRIS buffer - pH6.8 [on hold]

I was about to prepare buffer for milk enzyme and to follow prep method described on bio-rad. But then I became suspicious and came across tons of information that pH6.8 is not in effective pH range ...
2
votes
1answer
41 views

How to take a sample of a hot salt solution without it precipitating in the cooler glassware due to the difference in solubilities at different temps?

I'm doing an investigation to see the effect of temperature on the solubility product of strontium hydroxide. I made a supersaturated solution left in the oven overnight at 85°C for equilibrium to be ...
-1
votes
0answers
38 views

Parent and molecular geometry [on hold]

is the molecular geometry for carbon in formic acid trigonal planar. Also is the parent geometry for carbon in formic acid trigonal planar as well. Whilst the molecular geometry for hydroxyl oxygen in ...
0
votes
1answer
31 views

What is the reason for more stable keto form to tautomerise to a less stable enol form?

In the mechanism of SeO2 I have seen that a more stable keto form first converts to a less stable enol form and then yields a diketone. I have seen many other reaction where the reactant converts to ...
-2
votes
1answer
24 views

How do amphoteric compounds act as acids? [on hold]

According to my chemistry textbook, an acid is a compound that gives hydronium ion on dissolving in water but amphoteric compounds like ZnO do not yeild hydronium ion on dissolving in water . I ...
7
votes
1answer
43 views

How to determine the number of water ligands attached to Pd in palladium chloride aquacomplex PdClₓ · yH₂O?

Normally this can be achieved using UV-vis: there is a strong absorbance around wavelength 220 nm which varies based on the number of ligands. If the palladium concentration is too high, the solution ...
0
votes
0answers
36 views

Effect of solid in equilibrium

CaCO3 (s) = CaO (s) + CO2 (g) We know that pure solids quantity doesn't affect the position of equilibrium. But the application of pressure in gas does. If we add CaCO3 in the closed system, the ...
-2
votes
1answer
21 views

The pH scale/calculating pH level [on hold]

How much water do you need to add to 10 mL of a solution of HCl with a pH of 4 to change the pH to 5?
-3
votes
1answer
38 views

Important Stoichiometry question, just need formula or help and answer checking [on hold]

How many grams of Cobalt(II) chloride $\ce{CoCl2}$ is needed to make $\pu{0.645 L}$ with a concentration of $\pu{1.25 mol\:L^{-1}}$? (the molar mass of anhydrous $\ce{CoCl2}$ is $\pu{129.839 g\: mol^...
2
votes
1answer
92 views

How to determine the greatest d orbital splitting?

This question comes specifically from an IB Chemistry HL Paper 1 in May 2018 TZ1, namely question 8. Which complex has the greatest d orbital splitting? It gives 4 Complexes $\ce{[Fe(H_2O)_6]^{2+}}$,...
0
votes
0answers
38 views

Difference between Enthalpy and Heat [on hold]

I understand that enthalpy is a state function while heat is not. But what does this actually mean? More than just the basic definition of state function could somebody explain how being (or not being)...
8
votes
0answers
147 views

What is the largest coupled cluster calculation that has ever been done (as of March 2019)?

I am doing some research and trying to make sure the numbers I am reporting are accurate. I found that the paper by Sylvetsky et. al. says:[1] We were, however, able to complete a ...
-1
votes
0answers
16 views

Radical reactions involving terminal alkynes [on hold]

I have never seen this transformation before it isn't covered in the standard undergraduate organic chemistry so I wonder how the mechanism goes about?
0
votes
0answers
16 views

Calculating 'Air Dilution' Concentration to Estimate Final Odor Intensity [on hold]

Air flows at a rate of 1 l/min into a closed 40ml flask containing 2ml of amyl acetate serially diluted to 0.000002143% v/v concentration. The air-gas mixture then has the opportunity to escape trough ...
-1
votes
0answers
29 views

In the Joule-Thomson experiment, how is T1-T2 determined?

I figured out that H = U +PV is constant in this adiabatic condition. I am confused about the expression "T1-T2 is determined in this condition" I don't think it's an ideal gas, so delta(H) ≠ Cp ...
1
vote
0answers
14 views

Finding Pressure of M in a Charge Exchange

Ar (RE = 15.5 eV) is the reagent gas in a charge exchange experiment. If Ar+ reacts with anisole with a rate constant of 2.26x10-10cm3 molecules-1/s-1 and 65% of the Ar ions react in 25 milliseconds, ...
1
vote
0answers
20 views

Kinetic Shift of Simple Cleavage

What is the kinetic shift for the simple cleavage fragmentation if the ion source residence time is 100 microseconds, the time to reach the detector after leaving the ion source is 10 microseconds? (...
3
votes
0answers
38 views

Oxidation of diols using periodic acid

What are the orders of rates of oxidation with $\ce{HIO4}$ of the following diols? Explain with reasons. (a) $\ce{Me2C(OH)C(OH)Me2}$ (b) $\ce{Me2C(OH)CH(OH)Me}$ (c) $\ce{CH2(OH)CH2(OH)}$ (d)...
0
votes
0answers
16 views

Oxirane and ring opening

I have a problem given as :- I thought of a sn1 type mechanism in acidic medium and a sn2 pathway in basic medium . Am I correct or not . Please also check the mechanism according to which I formed ...
-3
votes
0answers
18 views

Explain how sp3 hybridisation occurs in carbon atom [closed]

Hybrisation in sp, sp2 ,sp3 and how they occur in carbon atom
2
votes
0answers
15 views

Metal catalysts used in C-H bond functionalisation [on hold]

Why are the late transition metals used for C-H bond activation/functionalisation? What atomic properties of the late TM make them attractive for coordinating C-H sigma bonds? Thanks.

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