All Questions

Filter by
Sorted by
Tagged with
-1
votes
0answers
29 views

Can hexadecanamide be toxic when ingested in tea? [closed]

This is an odd situation, but, at the advice of a doctor, I had some loose tea leaves tested for toxins and chemicals. The report came back and said that the tea leaves contained hexadecanamide, but ...
-2
votes
0answers
33 views

Are all geometrical isomers are diastereomers? [closed]

Till now I knew that all geometrical isomers are diastereomers. Is there any example of Geometrical isomers which are not diastereomers ?
2
votes
2answers
205 views

Lysozyme crystals versus NaCl

If someone has some experience with lysozyme crystals I would be interested in knowing whether any of the images below seem likely to be lysozyme. Solutions were made with powdered lysozyme ($\pu{50 ...
-2
votes
0answers
16 views

Stability of nucleophilic acyl substitution intermediates

If I have an acid chloride and I want to substitute it with ammonia to get an amide, I have a two step reaction. First the ammonia attacks at the electrophilic carbon giving me a tetrahedral ...
1
vote
1answer
42 views

Environmental properties of chemicals

I am trying to collect the environmental properties (GWP and ODP) of several chemicals. However, I am experiencing some problems with retrieving these properties for some fluids. For example, I cannot ...
0
votes
0answers
23 views

What rules should be followed ( in which order ) to check the correctness of a lewis structure [closed]

I know that : i) No. of electrons and charges must not differ from calculation using molecular formula ii) Central Atom is decided by in order: Least no. / Least Electronegativity / Highest Size then ...
0
votes
1answer
49 views

Mesylation of cyanohydrins [closed]

Is it possible to add methane sulfonyl chloride to benzaldehyde cyanohydrin, or add toluene sulfonyl chloride to form the tosylate group on the alcohol and then perfom a grignard reaction on the ...
-1
votes
1answer
55 views

How do I balance redox equations with three reactants?

Could anybody please explain me the concept of balancing redox reactions with three reactants? Either some solving steps or even the solution would be very appreciated. For example, I don't know how ...
-1
votes
1answer
62 views

SN1 mechanism on 3,5-dimethylbenzyl bromide [closed]

I wanted to see how to make the product on the right so my thought was to have an SN1 reaction to remove water and have the bromine ion attack making the product on the right hand side. Is this ...
-1
votes
0answers
22 views

The Ionisation enthalpies of the third period elements (Mg, Si) are given 737 and 789 respectively. So the I·E of (Al) be more close to 586 or 750? [closed]

This question made me unclear because there were to be many factors associated with it such as screening effect , Z.eff , fact that s-orbitals are more attracted towards nucleus than p-orbital. I ...
-3
votes
0answers
24 views

Why in a Lewis Dot structure central atoms want highest possible covalency [closed]

Why in a Lewis Dot structure central atoms want highest possible covalency. Is this because formation of bond is exothermic and hence a higher covalency means extra stability?
-2
votes
0answers
13 views
1
vote
1answer
153 views

Mechanism for alcohol synthesis via terminal acetylene reaction with sodium amide followed with epoxide and protonation

If anyone can give me some guidance here, it'd be much appreciated. I know the NaNH2 would dissociate and the NH2- base would deprotonate the terminal acetylene. I'm assuming the resultant product ...
-1
votes
0answers
37 views

Michael Addition- which hydrogen atom is removed

I have the following Michael addition reaction and wanted to know which H atom would be removed. I know that the more acidic H atom is removed and the more stable intermediate is formed which then ...
-1
votes
1answer
115 views

What is "gram atom of an element"? [duplicate]

I've seen so many answers on Quora that got me lost : 1st answer : The three are similar. Gram atom.... Take the atomic mass of an element and express it in grams (sodium for example atomic mass is 22....
0
votes
1answer
29 views

Endothermic reaction with dV < 0 [closed]

I am looking for an endothermic reaction dH > 0 for which the net volume change is negative, e.g. gases reacting to form a liquid. Does anybody have an illustrative example?
0
votes
0answers
27 views

Why do gases generally dissolve better in cold water, while solids dissolve better in hot water? [closed]

I have noticed this since I was a little kid, yet have never come across a satisfactory answer....
-3
votes
0answers
18 views

Ni(NH3)4(H2O)2]2+ and the anion Cl- | Formula of coordination compound containing cation and anion and how many possible geometric isomers are there? [closed]

What is the formula of the coordination compound containing cation [Ni(NH3)4(H2O)2]2+ and the anion Cl-? How many possible ...
-3
votes
0answers
19 views

Efficiency of using flame for lighting [closed]

Is a hydrogen/oxygen flame better or worse than an incandescent bulb in terms of lighting efficiency.  Or to put it another way, if both produce the same amount of light, which will be hotter? Or is ...
-3
votes
0answers
20 views

General Chemistry 1: Stoichiometry [closed]

What is the limiting and excess reactants in the reaction between 3 moles of NH3 and 6 moles of CuO? Show your solution.
-3
votes
0answers
21 views

Calculate the quantum yield [closed]

I've come this far: A = log10(I0/I) → I = I0/10A → Absorbed light = 1-I = 0.89529 2 [mW/cm2]x(Absorbed light) = 1.79058 [mW/cm2] 360 nm = 5.5179e-19 J/photon 10 cm2 x 1.79058 [mW/cm2] = 17.9058 x 10-...
0
votes
0answers
6 views

Calculations of the charge transfer in GAMESS US [migrated]

I'm trying to calculate the effective transfer integrals $J_{\text{eff}}$ from monomer A to monomer B within dimer AB by using GAMESS US: $$J_{\text{eff}}=\frac{J-S\cdot (e_1+e_2)/2}{1-S^2},$$ where $...
-1
votes
0answers
28 views

Type of reaction involving hydrocarbon radicals and hydrogen ions [closed]

I've been analyzing how the percentage mass of hydrogen in the radical hydrocarbon affects the overall enthalpy change of the following reaction: $$\ce{C_xH_y^- + H^+ -> C_xH_{y+1}}$$ I have the ...
0
votes
1answer
77 views

Contradiction to law of chemical equivalence in double titration [closed]

A common reaction which is studied in titration is $$\ce{Na2CO3 + 2HCl -> 2NaCl + H2O + CO2}$$ This reaction requires the use of two indicators (phenolphthalein and methyl orange) to mark two ...
0
votes
0answers
6 views

NBO Calculation failing (ATDIAG DISCRD) [migrated]

I'm trying to perform NBO calculations on a bimetallic complex to evaluate bond orders. However, while I've previously done NBO calculations to obtain partial charges which worked without problems, ...
0
votes
0answers
51 views

Confusion about using Nernst Equation in Hydrogen Electrode [closed]

I was trying to calculate the potential of hydrogen electrode when $\pu{0.1 M}~\ce{HCl}$ was present in the hydrogen electrode at $\pu{300 K}.$ The chemical equation is $$\ce{H2 <=> 2 H+ + 2 e-}$...
-1
votes
1answer
20 views

How rate of absorption remains same throughout the process?

While reading surface chemistry, I got Rate of adsorption is high at begining and then decreases till equilibrium is attained . On the other hand , rate of absorption remains same throughout the ...
0
votes
0answers
21 views

If I want to determine the concentration of CO2 in mass spectrometry. Can I only use the m/z 44 or do I need to consider all of the fragments? [closed]

I'm building the calibration using Ar as a carrier gas and varying the concentration of CO2 by adjusting the volumetric flow rate, e.g, 30 mL/min of Ar; 0, 40, 60, 80 ml/min of CO2. After that, I ...
-1
votes
0answers
21 views

Avoided Corssing in Potential Energy Curves and Crossing in Permanent Dipole Moment [closed]

I am currently studying the electronic structure of a diatomic molecule. I am noticing that when the potential energy curves of 2 states avoid each other at a certain point, we obtain a crossing at ...
0
votes
0answers
21 views

Why does the same type of hybridization appear in both Valence Bond Theory and Molecular Orbital Theory?

I was reading about Molecular Orbital Theory, and saw that you can treat a central atom's atomic orbitals as hybrid orbitals in order to simplify the process of creating molecular orbitals by no ...
0
votes
0answers
74 views

The necessary energy required to ionize 1g of potasium in its fundamental state if the ionization energy is given

The energy of ionization of the potassium is $\pu{6.94\cdot 10^{-19} J/atom}.$ Find the necessary energy to ionize $\pu{1 g}$ of potasium that is found on its fundamental state. Attempt. I really ...
-2
votes
0answers
11 views

Chemical Equilibium [Equilibrium Constant] [duplicate]

During heterogenous equilibrium, we take active mass of pure solids and liquids as 1. I don’t understand what is meant by pure liquids here. Please guide me how to write equilibrium constants in these....
0
votes
0answers
79 views

Electrolysis of nitric acid solution to make sustainable ammonia efficiently [closed]

For sustainable and efficient ammonia ($\ce{NH3}$) or ammonium hydroxide ($\ce{NH4OH}$) production from the electrolysis of nitric acid ($\ce{HNO3}$) solution, what are the best and easily accessible ...
2
votes
2answers
104 views

Elucidating an unknown compound using 1H- and 13C-NMR spectral data [closed]

I am currently struggling with the following NMR spectrum for this compound: I know for sure that we should multiply the integrals of the hydrogen atoms by four, and that the compound contains at ...
0
votes
1answer
112 views

Cobalt glass colour of potassium as

Question: Cobalt glass colour of potassium as: A) Crimson red B) Lilac C) Apple green D) Brick red I thought option B as true because on flame test, potassium gives lilac colour. But the given ...
0
votes
0answers
14 views

An efficient process to extract coconut oil [migrated]

I have tried to extract coconut oil. Below is the process I have followed. Ground the coconut flesh with some added water. Milked the ground coconut flesh by cold pressing it and filtering all big ...
0
votes
1answer
34 views

How does addition of side chains affect solubility and processibility of polyphenylene vinylene?

I am studying electrical engineering and physics. In a recent lecture I was told the $\ce{OC1C10}\text{-PPV}$ molecule has the chains added to the oxygen atom down below because it allows for ...
2
votes
0answers
82 views

Is syn addition possible with Br2? [closed]

How is this reaction correct? I have studied until now that with $\ce{Br2}$ only anti-addition takes place.
-1
votes
1answer
119 views

What is the mechanism of paracetamol synthesis from N‐acetylsulfanilic acid? [closed]

C can be converted to D with NaOH and heating at 300 °C. What is the mechanism of the reaction?
0
votes
1answer
43 views

How is nitrogen gas passing through condensed water in the U-Tube while reducing metal oxides with ammonia gas?

In my school chemistry book, the experiment about the reduction of metal oxides with ammonia has a diagram of the set up as follows: $$\ce{NH₃ + CuO → 3Cu + 3H₂O + N₂}$$ The tube entering the U-tube ...
-1
votes
0answers
22 views

Which of the following reactions is a redox reaction? [closed]

Which of the following reactions is a redox reaction? a- Scandium with water b- Ag with HCL c- Cu with HCL d- all the above Guys, I dunno how to solve this question, How do I know if this is a redox ...
3
votes
1answer
64 views

Predicting time taken to reach equilibrium

Consider the following reaction, $\ce{A <=>[k_f][k_b] B}$, $k_f$ and $k_b$ are the rate constants of forward and backward reactions respectively. Let the initial concentration of $\ce{A}$ be $a \...
-3
votes
0answers
52 views

Why is the symmetric form of cyanamide favoured? [closed]

This process that is technically important is called the Frank–Caro process. $$\ce{CaCN2 + 3H2O -> CaCO3 + 2NH3}$$ The equilibrium favours the more symmetric structure of $\ce{HN=C=NH}$ and $\ce{N#...
-2
votes
0answers
13 views

What is the number of 3d electrons of the transition metal ion in the following complex: [closed]

What is the number of 3d electrons of the transition metal ion in the following complex: [Cr(OH2)4Cl2] Im confused how to count the electron config if it is complex. is there a very easy way to ...
0
votes
1answer
43 views

Orbital angular momentum of an electron in s-orbital

I'm a beginner in quantum mechanics, and I'm pretty much confused with the orbital angular momentum of electron in s-orbital of hydrogen atom. I've read that average angular momentum of an electron in ...
-2
votes
0answers
24 views

Find avg. Bond energy of Xe-F if enthalpy of formation for XeF2, XeF4 and XeF6 are given [closed]

FULL QUESTION : I) The standard enthalpies of formation of gaseous XeF2, XeF4, & XeF6, are -108, -216 , -294 kJ/mol respectively and the bond energy in F2, is 159 kJ/mol. Calculate the average Xe-...
-2
votes
0answers
23 views

Does pressure affect rate in equilibrium reactions? (in rxns where it causes a shift in position of equilibrium) [closed]

In the haber process if I increase the pressure, it will cause a shift in equilibrium to side with less gases, however is there any change in rate? Edit: I searched online before this question and ...
0
votes
1answer
61 views

Why do isosteric molecules have similar shapes? [closed]

Isosteres (Definition): Isosteres are atoms, molecules, or ions of similar size containing the same number of atoms and valence electrons.[1] Questions: A. Why ...
1
vote
0answers
48 views

Will all aldehydes and ketones give 2,4-DNP test?

I've recently gone through 2,4-DNP test for aldheydes and ketones on Byjus: An aqueous solution of 2,4-dinitrophenyl hydrazine (DNP) is known as Brady’s reagent. It reacts with carbonyl compounds (...
-1
votes
2answers
54 views

Intesive Properties - Temperature [closed]

Why is the temperature of a sample of matter intensive? I don't think it would be extensive, but I also don't see why it would be intensive, either. It's a very basic and easy question, but I can't ...

15 30 50 per page