# All Questions

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16 views

### Is coating titanium with PbO2 better alternative to the graphite substrate one?

I want a good anode for my chlorate cell. I tried coating graphite with PbO2 but without success. So I was wondering about using titanium as substrate. Is it better then graphite, also is it easier to ...
23 views

### Comparing the order of intermolecular forces [closed]

Order of intermolecular forces: $$\ce{CO2} > \ce{CH4} > \ce{N2}$$ Here, van der Walls force increases with molecular size. Thought $\ce{CH4}$ is $16 \,\rm g$, it has stronger molecular force ...
41 views

### Global reactivity parameters from open shell DFT calculations using Koopman's theorem

Koopmans' theorem is a useful approach to calculate the global reactivity parameters from the HOMO-LUMO energies. My question is, does it apply to the open-shell systems where we get two sets of ...
34 views

### Finding the maximum mass of copper(II) nitrate that can be produced from a given mass of copper [closed]

I have the following chemical equation: $$\ce{Cu(s) + 4 HNO3(aq) -> Cu(NO3)2(aq) + 2 H2O(l) + 2 NO2(g)}$$ The mass of copper in the equation is 0.6355 g. I am trying to find the maximum mass of ...
20 views

### Any element do not form four covalent with other atom. Why? [closed]

Any element do not form four covalent bond with other atom. Why? PLEASE GIVE ANSWER I AM STUDY IN 11 CLASS
25 views

### Separate less volatile component from distilling a mixture [closed]

Is it a strict rule that when we boil a mixture of two liquids, with one being less volatile than the other, the more volatile vapour has to form the greater portion of the total vapours? If it is so,...
12 views

### How to confirm experimentally that a hemi-acetal compound has formed?

I have read that under mildly acidic or alkaline conditions alcohols can attack aldehydes/ketones to produce hemi-acetals. But the reaction is reversible, so the reactants and the hemia-cetal are in ...
5 views

### What is the potential of Zn- Hg electrode if 80% of zn-hg is in contact with zn2+ ions of 0.06 M concentration [closed]

Effect of immersed surface area of the electrode on the potential
37 views

### How do I name a substituent which is a cycloalkane which is attached by a chain of more than one carbon?

Above is a picture of an alkane. How would I name this using IUPAC rules? I understand how to name other substituents such as (1,1-dimethylethyl) and some other methyl groups, but I don't know how to ...
14 views

### What makes a chemical reaction reversible? [closed]

Is there a way to determine whether a chemical reaction will be reversible or not?
18 views

### Connolly surface for a deuterated/tritiated molecule [closed]

peoPle did not liKe van der Waals and covalent radii for deuterium and tritium ("hardly worth pursuing" was one coMment) so perhaPs I sHould ask my aCtual quesTion instEad, I want to comPute the area &...
35 views

### Based on Molecular Orbital Theory , how is it decided that the double bond in O2 molecule has one sigma bond and one pi bond?

My Chemistry textbook says this in regard to a C2 molecule: It is important to note that double bond in C2 consists of both pi bonds because of the presence of four electrons in two pi ...
31 views

### Using a the particle in a box - one dimension, to calculate the zero point energy of an hydrogen atom

I have been tasked with using the one dimensional particle in a box model to calculate the zero point energy of an hydrogen atom with different sizes. Using the formula $E_1=h^2/(8mL^2)$ for a box ...
20 views

### Equation for predicting electron distance [closed]

Say that I have a Hydrogen Atom. We know from the electron cloud model that the electron has a certain probability of being in a certain area, and I've always been told that this probability can be ...
28 views

### Psi4 gradient calculation with complete basis set? [closed]

I'm trying to set up a gradient calculation for psi4. In my input.dat file, I have tried the following keywords: set basis cc-pVTZ gradient('CCSD(T)') which is ...
15 views

### Fat polymerization vs hydrolysis and temperature change

I have an experiment on fats that I have to do in a few hours and I am very lost between fat/oil (lipid) polymerization due to high temperatures and hydrolysis. It appears that both result in the ...
48 views

### How does acetone help to make a liquid cleaner stronger? [closed]

Acetone, as a solvent, seems to behave somewhat different than other solvents. It seems to solve things other unpolar solvents do not. For example, I have two cleaner sprays from the same brand, and ...
45 views

### van der Waals and covalent radii for deuterium and tritium

After a lot of searching on the Internet, I find that there seems to be no (easily accessible) reference for the van der Waals and covalent radii for deuterium and tritium. I saw a few notes that ...
26 views

### Resonance Structures of Molecule [on hold]

I'm a preparatory O-Chem class and we've been studying resonance structures by using arrow pushing, and the professor gave us this molecule to find the possible resonance structures. All the lone ...
21 views

### Using a weak acid to prevent the precipitation of Mg(OH)2

I have this exercise in my chemistry book, and I have been staring at it for so long but unfortunately I have no single idea what to do and where to start. I will be so thankful for any help. $0.05$ ...
23 views

### Why are the OV and VO blocks of the CIS 1RDM zero?

I know the reduced density matrix has the form: $$\gamma(\alpha,\beta) = \langle\Psi_N|c^{\dagger}_{\alpha} c_{\beta}|\Psi_n \rangle$$ but when $\Psi_N$ is the configuration interaction singles (CIS)...
20 views

### Stability between Nf5 and Of4 [closed]

Question-: Which is more stable Nf5 or Of4 This question arose in my mind and i have no idea about this.Please tell the reason also. I could only think that both of them can not exist.
38 views

### Is propanol 1-2 diol 178 the same as propylene glycol?

I clean vinyl records in an ultrasonic vinyl record cleaning machine the manual states it uses propanol 1-2 diol 178 as a surfactant. I think this is the same chemical as propylene glycol. Is it? ...
22 views

### Using MP-AES, can I accurately say I've found a metal concentration on one wavelength and not another?

I've been given the opportunity to use an MP-AES for metal detection. I'm testing traces of metals in plants. The plant matter is digested so I have a liquid solution, I expect there to be a lot of ...
17 views

### Importance of high speeds molecules in Maxwell's distribution [closed]

Why does the Maxwell distribution go to zero at very high speeds ? What such a molecules would do to the wall
16 views

### What is the relative position of the antibonding orbital with respect to the bonding orbital? [closed]

I learnt about bonding and antibonding orbitals today in school and while I understood the general concept, I didn't understand how they're positioned with respect to each other. For example, in this ...
40 views

### To move one electron in one H atom from the ground state to the second excited state, 12.084 eV are needed

How much energy is needed to cause 1 mole of H atoms to undergo this transition Assume Bohr's model of quantisation The energy for transition is $$1312\left(\frac{1}{n_1^2}-\frac{1}{n_2^2}\right)$$ ...
40 views

### What is the recommended way to put away a beaker of very hot water? [closed]

Let's say I have done an experiment and am now left with a beaker of very hot water sitting on a hot plate. How do I put this away ? I should start by saying that letting it cool naturally is not an ...
16 views

### What noble gas reactions exist? [duplicate]

It's often said that noble gasses are mostly unreactive, but mostly is not always, so what are the exceptions?
19 views

### Why do some compounds sublimate whereas some do not? [closed]

Carbon Dioxide sublimates and so do some other compounds. Compounds like Water do not sublimate. Why is this the case? Thanks
24 views

### How can I obtain CaCO3 from CaO? [closed]

How can I obtain CaCO3 from CaO? I feel the backward rxn of decomposition of CaCO3 won't really be feasible. Is there any other way?
21 views

### gibbs free energy equation implication [closed]

Why is RTlnQ an energy term? Also how does this term actually affect the amount of energy released/absorbed in a reaction? It seems counterintuitive because somehow changing reactant: product ratio ...
18 views

### Why does ice melt faster when exposed to a liquid than a gas, even if the liquid is colder than the gas? [closed]

For example, if you take frozen berries crusted in ice and put them in a bowl, exposed to air at room temperature, the ice basically doesn't melt. However if you pour milk - colder than the air - on ...
18 views

### Enantiomeric excess catalysed

Enantiomeric excess is defined as $$ee = \frac{[R]-[S]}{[R]+[S]}$$ I found this problem in an IChO paper: "When using the enantiomerically pure (BINOL)Al(OiPr) as a catalyst for reduction of ...
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### QM9 dataset with chirality

I am trying to find chiral centers of molecules in QM9 dataset. Browsing their SMILES representation, I noticed SMILES yield using datasets.get_qm9(GGNNPreprocessor(), return_smiles=True) don't ...
20 views

### Electrolysis and Electrodialysis setup help [closed]

I am attempting to design a device that can take in any form of water, whether it be pure H2O, salt water, or pool water, and spit out Hydrogen and Oxygen gas. From my research, I've only found one ...
11 views

### How do you use MacConkey's agar to test yogurt? [closed]

I am in Secondary school and we are testing radiation effects on yoghurt and one thing my teacher reccomended was testing through MacConkey's agar to see what happens. 1) Can someone explain in lay ...
36 views

### Method for making graphene by reducing carbon dioxide on gallium surface [closed]

I had an idea where you take gallium in a vacuum and while it’s under a vacuum you spread it out across a flat surface such as a glass slide. You would want to spread it while under a vacuum to ...
22 views

### Differences Between RainX and RainX Anti-Fog? [closed]

I have a question pertaining to chemistry in a practical way. As I was unable to find a more suitable community to ask, I shall ask it here. RainX, as you may already know, is a compound applied to ...
29 views

### Obtaining conformational energy from Newman projections in first place

In this source, the conformational energy from Newman projections is obtained. Is there a formula or quantum chemistry approach to obtain the values in first place (pretend that I don't know the ...
19 views

### Basic strength of pyridine and Imidazole [closed]

Why not conjugate acid of pyridine is stablised by conjugation just like conjugate acid of imidazole which is stabilised by conjugation?
26 views

### Boiling in a closed tube [closed]

If I'm boiling a thiazole at 145 degrees in 'a closed tube' with hydrochloric acid...what would the required apparatus be to get it to maintain at 145 for 3 hours? I read this online about "...
20 views

### How to create root surfaces? [closed]

I want to create a supercell of sqrt{2} x 1 from a unit cell structure using atomic simulation environment (ASE). Can anybody please suggest me how to create this kind of root surfaces in ASE? Or is ...
28 views

### Surface modelization of an electrode

I am trying to model the interaction between an electrode and a saline solution through an RC circuit. A reference electrode is placed in the saline solution to measure the voltage between the ...
42 views

### Reaction between CuSO4.5H2O and NH3

Today in the laboratory we did a confirmatory reaction for Copper (II) in CuSO4. The reaction we carried out was adding NH4OH to a little of original salt solution. So the reaction that took place is ...
71 views

### What happens when a super-critical fluid is compressed?

Suppose that I have some substance with a critical temperature of 20°C. That means above that temperature, the substance exists neither as a gas nor a liquid, but instead as a super-critical fluid. ...
31 views

### CNDO/2 clarification

I wrote a piece of code on RHF using Python a while back, and figured I'd extend it to also implement CNDO/2 (yes, I know it's old but I figured it'd be easier for me.) The approximated Fock matrix ...
13 views

### Potassium Dicromate reacting with Iron both in solutions. ( Redox) [closed]

When Iron Is reacted with Potassium Dichromate, A pale green solution is mixed with an Orage solution to form a Green solution at the end. What is the Ionic half equations and the full ion equation? ...