# All Questions

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5 views

### How can we convert methanamine to ethanamine?

I searched this question everywhere and I found that use HNO2 in the first step to convert methananmine to methanol but as far as I know (and verified by other sources) this reaction is not feasible ...
2 views

### do electrons in different orbitasl in a same subshell have same energy

In valence bond theory, I suppose that electrons in say, 2px and 2py have the same energy because of the same structure of orbitals. But what about 3dxy and 3dz^2? Do they also have the same energy? I ...
6 views

### Why was Dalton's atomic theory accepted?

Dalton's atomic theory reversed the way we had been thinking about matter at a fundamental level. But I have tried to find the specific experiments that he performed and used to come to this ...
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### general organic chemistry nitrobenzene less reactive than toluene

Assertion: Nitrobenzene is less reactive than toluene towards electrophilic substitution reactions. Reason: -NO2 group is meta directing whereas -CH3 group is ortho, para directing.
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### Band structure of d-block elements

Can we make a band structure of d-block elements or is there something which complicates things?I am asking this because I have found something like this which implies that we cannot follow the same ...
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### what is S p d f

So I know how to make the atoms configuration and all but what is s p D f orbitals I can't understand it and why do we have to repeat it like we write the configuration of oxygen like this 1S² 2S² 2P⁴ ...
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### Find gas pressures of injection knowing mixture pressure without knowing volume

I am asking for help because I couldn't find the answer even on the Internet ? Let's say we have : a gas 1 moving inside a pipe (we don't know the geometry) at mass flow rate $Q_1$ and temperature \$...
12 views

### Number of pi electrons in this conjugated system

I wondered if the electron lone pairs on the oxygen atoms also counted as pi electrons since resonance structures exist where these lone pairs can be delocalised over the molecule? If so how would ...
8 views

### Structure-Activity Relationship of Chlormephos and Parathion

According to the book "The Chemistry of Organophosphorus Pesticides", the insecticide Chlormephos (S-(chloromethyl) O,O-diethyl phosphorodithioate) has an oral LD50 in rats of 7 mg/k. ...
13 views

### Calcium hydroxide questions (as it relates to corn and nixtamalization)

Please pardon my chemistry ignorance! I actually have done a lot research on these specific topics, but can't find anything definitive--anywhere! When adding calcium hydroxide to water and corn for ...
10 views

### Can -NH3+ be a meta directing group [duplicate]

As the groups which are cations commonly act as meta directors in benzene reactions, can -NH3+ be a meta director?
11 views

How does a negetive sign appear in rate constant I mean in this $$Rate=\frac{d[A]}{dt}=-K[A]^2$$ While what I know according to rate law is that $$Rate= K[A]^2$$ Please help me
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### acid-base most suitable indicator selection [closed]

I struggle with indicating the most suitable indicator for titration, and I also found it calculated by different ways in many references and don't know the correct way, so e.g 0.100 M HOCl (Ka = 3.5 ...
6 views

### what is steric inhibition of resonance and how does it affect the acidity [closed]

I have just come across steric effects in organic chemistry however I don't understand the logic behind it. Is it possible for anyone to explain it and if possible can u link down some resources for a ...
11 views

### Crystals formed by sodium chloride vs those formed by cesium chloride? [closed]

I can't find the similarities and differences. Not sure what I'm supposed to notice between the two types of crystalline structures.
23 views

### Betaine HCl solution at neutral pH

I was trying to make a 2M solution at pH 7.5 of Betaine HCl. I started by weighing out the appropriate amount of Betaine HCl, added some water and started stirring. At this point, the pH of the ...
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I have a big worry that I would really appreciate your opinion on. I just moved in to a new apartment and when I heated up the oven for the first time this horrible very strong smell of Chemicals ...
24 views

### What is Radioactivity and radioactive decay and why a drinker of Atomic energy suffers biologically? [closed]

Radioactivity is the phenomenon of the spontaneous disintegration of unstable atomic nuclei to form more energetically stable atomic nuclei. radioactive decay is a highly energetic, statistically ...
26 views

### How can I find out how much caffeine is in my decaf tea and coffee?

I know that the decaffeination process is not perfect and that it leaves some caffeine. I've looked online and there was a company in 2009 that offered caffeine test strips but they seem to be no ...
7 views

### Hydration of Alkenes [closed]

Why does phosphoric acid doesn't behave as a dehydrating agent in hydration of alkenes to alcohol? Plz answer as soon as possible. Test tomorrow.
32 views

### I dont understand GaAs structure

This is GaAs.The purple balls are As atoms and the brownish balls are Ga atoms.As has 5 valence electrons but here it clearly makes 4 bonds.Ga has 3 valence bonds but some atoms of the middle Ga atoms ...
12 views

### What is the anodic reaction of aluminum in water

Standard electrode potentials are reported for materials that are not usable as actual electrodes in water because they react spontaneously and rapidly. https://www.engineeringtoolbox.com/electrode-...
10 views

### What is the correct way to calculate log P of a drug?

Two 3ml samples of 1%w/v solution of ibuprofen in octanol were prepared, a pH 2 buffer is added also. 0.5ml of the octanol layer is taken and diluted with octanol to 5ml Equation of the line for the ...
17 views

### What chemicals can be safely released into the air or sea? [closed]

I've found lots of prohibitive documents about what is not alowed to be released as it is pollutant. Is there a list of what is allowed? Solids, liquids and gases. Is there some sort of rule of thumb? ...
19 views

### Do the cathodes of all batteries increase in mass as the battery is used?

I understand the mechanism behind the cathode's increasing mass in many batteries. As the cathode receives electrons, ions are reduced to form atoms. In short, more electrons equals more mass in the ...
11 views

### Standard cell potential- why do solutions contain ions of the same element as the electrode?

All of the examples I have encountered so far in calculating the standard cell potential include solutions containing ions of the material making up the electrode such as Zn2+ and Zn electrode. What ...
26 views

### SiGe small concentration of Ge

Suppose we have Si doped with Ge at small concentrations(1M to 1).The band diagram of this new substance will be almost identical to pure Si,however which will be the energy of the 3d electrons of Ge?...
18 views

### Exprerimental metal surfaces in pdb/xyz

I need the coordinates of palladium slab (both 100 and 111 surfaces) in xyz or pdb format. Are there some archive of experimental data? Thank you
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### Does cinnabar react with iodine?

Does cinnabar react with bromine and iodine to form elemental sulphur? This reaction was described in "Explorations in the history of science and technology in China" but I have doubts...
21 views

### Does increasing one of the electrolytes in a galvanic cell increase the voltage?

I would like to know how you could increase the voltage in zinc and copper galvanic cell: $$\ce{Zn(s) + Cu^2+ → Zn^2+ + Cu(s)}$$ I know that temperature and surface area is a factor that affects the ...
30 views

### Why does whey protein powder make porridge much less viscous?

When I mix whey protein powder into warm porridge (that I cooked in the microwave), the thick porridge becomes much less thick. I searched this, and I found several forum threads discussing this too ...
25 views

### Why is the ester carbonyl peak in benzocaine IR spectrum so low>

Having looked at multiple IR spectra for benzocaine, I am struggling to understand why the carbonyl C=O peak is so low in the spectra compared to where an ester carbonyl group usually is on other IR ...
17 views

### Why are Methyl vibr. modes called r modes and methylene vibr. modes called d modes

I am coming from a chemical background and currently work in the field of vibrational spectroscopy. When I talk to fellow physicists or chemists I always encounter the same question. "Why are the ...
22 views

### Can be elektron alloy used to make sodium?

I would like to know, if I can use elektron alloy (mostly contains about 90% of Mg) to make sodium. I have seen tutorials how to make sodium fron NaOH and Mg powder, but I do not have Mg powder... Mg +...
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### Photoelectric cells

I've read about photoelectric cells, and most of the sources say that Potassium and Cesium can be used as electrodes in the same. But why not Rubidium? The abundant isotope of Rb (72.2%) is not ...
12 views

### Entropy change in isothermal process

This is a screenshot of my chemistry course ppt. Considering point 2 - I don't quite get the meaning of it, could somebody please explain it to me?
19 views

### Stereochemistry of the product of crotonic acid with bromine

Is there a a simple rule for determining the stereochemistry for the product of a reaction between an unsymmetrical alkene like (2E)-but-2-enoic acid and bromine (anti reaction)? If it's an anti ...
13 views

### Organic Based Photocathode

What organic molecules have a relatively small work function, preferably in the visible spectrum? Polycyclic aromatic hydrocarbons are in the low UV spectrum, making it unsuitable for the photocathode ...
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### SDBS database Disclaimer/Entrace page

I'm trying to learn IR spectroscopy by examining spectra of some organic compound in SDBS, a great website but the disclaimer page pops up for literally every search I do and It does not seem to have &...
20 views

### Accidentally sprayed the wrong product in my mouth [closed]

I sprayed the wrong product in my mouth the other day. It was a spray hand cleaner. Noticed the mistake right away and immediately spit it out and then rinsed my mouth. But even so, my tongue and ...
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### Calculation regarding doping(Synthesis of Cu doped ZnO using Coprecipitation method)

I have to prepare 1mol% Copper doped ZnO using the Coprecipitation method. I am using Copper acetate and Zinc acetate as the salts and Sodium Hydroxide as the precipitation agent. I need approximately ...
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### Why do 4d and 5d metals have more orbital overlap than 3d because of size?

When considering the electrical conductivity of metal oxides, they will conduct better if the metals orbitals can reach each other to overlap. Whether this can happen is contributed to by a couple of ...
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I work in a lab where I use methylammonium lead triiodide dissolved in DMSO and GBL. I know DMSO penetrates skin easily, and obviously lead is toxic. Today I accidentally splashed some on my arm, and ...
15 views

### Procedure to buffer 1L with pH=6 from 21.2g of sodium carbonate? [closed]

I need the procedure to buffer 1L with pH=6 from 21.2g of sodium carbonate. Are available solutions of NaOH and HCl 2,0mol/L. Also, what would be the concentrations of H2CO3, HCO3 and CO3 in that ...
69 views

### If you wanted to increase the pH of a weak acid by 1, how many times should you need to dilute it? [closed]

For strong acids, I know it's 10 times, but not sure how to quantify it for weak acids.
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### Why does the pH of the endpoint decrease when temperature of the titration is increased?

I was doing an experiment in chemistry class involving titrations. I would heat up different samples of vinegar and titrate them using NaOH. The trend that I found was how has temperature increase, ...
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### Compressibility Factor and Generalized Compressibility Chart

From my understanding, the compressibility factor is defined by $$Z=\frac{pv}{RT}=\frac{p\bar{v}}{\bar{R}T}$$ It can also be defined by the ratio of the real molar volume of a gas to the ideal molar ...
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### organic chemistry- iupac naming

How do you write tertbutyl in iupac naming? I know for iupac naming, I would need to write the substituents in alphabetic order, but would tertbutyl be considered t or b?