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20 views

What is the pressure of the dry gas alone? [closed]

A 550.mL sample of oxygen is collected over water at 25ºC and 560.0 torr pressure. Vapor pressure of water at 25 ºC = 23.8 torr)
1
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0answers
22 views

thermodynamics problem [closed]

The boiling point of a substance $X$ at 1 atm pressure is $500 k$ . The enthalpy of vapourisation at the boiling point of $X$ (l) is 80 kj/mol .The molar specific heat of $X(l)$ = $5 × 10^{-3}$ kj/mol ...
4
votes
0answers
42 views

can a vapour denser than air evaporate in a closed chamber? [closed]

Imagine a closed container filled with air. There is some liquid substance on a bottle placed on the floor of the container. Let's heat the liquid until it starts to evaporate. Let's say 20% of the ...
-1
votes
0answers
9 views

25.00 mL of a 0.150 M HCN solution is titrated with 0.100 M KOH solution [closed]

25.00 mL of a 0.150 M HCN solution is titrated with 0.100 M KOH solution. The Ka of HCN is 4.0 x 10^-10 a)What is the volume of KOH needed to reach the equivalence point? b)What is the initial pH? ...
0
votes
0answers
25 views

Reactivity of dinitrogen vs carbon monoxide [closed]

As far as I understand, the 3-fold bonds in $\ce{N2}$ (dinitrogen) and $\ce{CO}$ (carbon monoxide) are the strongest among all bonds. This explains why $\ce{N2}$ is inert and not reactive at all. But ...
0
votes
1answer
15 views

Heterogeneous ion solution

I am a college student and for my chemistry of solutions class, I had a lab where we had to titrate orange juice to check the calcium content. However, the experimental results are 20% off the ...
-1
votes
1answer
28 views

Descale: Vinegar vs citric acid and temperature [closed]

The core of my question: What is the best temperature to descale with vinegar / citric acid? I often read to use vinegar essence with 25% acidity, dilute it with water and then let it soak. Sometimes ...
0
votes
1answer
27 views

Conditions for Complete hydrolysis of salt [closed]

My text book says that the cations (or anions) which are stronger than hydronium ion(or OH-) and their conjugate base (or acid) being very much weaker than water show complete hydrolysis. While the ...
-3
votes
1answer
68 views

Preparation of potassium cyanide from potassium ferrocyanide via HCN method [closed]

Does anyone have any experience with the preparation of potassium cyanide from potassium ferrocyanide via HCN method? I did some math and am going to proceed eventually, any advice would ...
0
votes
1answer
48 views

laser diode problem [closed]

I'm a student studying chemistry, i'm working with diode laser to look at emission spectra for certain complexes. i'm using integrating sphere as my setup, when i use the 405nm diode laser output of 4....
-1
votes
0answers
17 views

How do you convert 5% H2O2 to 3%H2O2 using C1C2=V1V2. And how to you then know how much H20 parts to add to H2O2? [closed]

How do you convert 5% H2O2 to 3%H2O2 using C1V1=C2V2. And how to you then know how much H20 parts to add to H2O2?
2
votes
1answer
40 views

Linear combination of eigenfunctions

In the textbook "Molecular Quantum Mechanics" by Atkins and Friedman [1, p. 11], it says in chapter 1: … a general function can be expanded in terms of all the eigenfunctions of an operator, a so-...
1
vote
1answer
83 views
+50

How to prepare cyclohexanone without starting with cyclohexanol?

What's an easy way to prepare cyclohexanone if I dont have direct access to cyclohexanol? I'm willing to synthesize cyclohexanol from more common materials, then make cyclohexanone from that. But most ...
1
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0answers
22 views

What are some possible classification tests that one can use for o-nitrobenzoic acid?

I have analyzed an IR spectrum and found out that my compound (o-nitrobenzoic acid) has a nitro group, carboxylic group, and benzene ring. I was curious to know: if regioselectivity effects the ...
-5
votes
0answers
55 views

Walk Me Through This Problem Please [closed]

1) Calculate the number of grams of Fe that are produced when 57 grams of FeO is reacted with excess aluminum in the following reaction: 2Al(s) + 3FeO(s) -> 3Fe(s) + Al₂O₃(s) 2) Calculate the number ...
0
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0answers
22 views

Formation constant of Eriochrome Black T Complexed with Pb (II) [closed]

What is Eriochrome black t’s formation constant when complexed with Pb (II)? If Eriochrome was placed in solution with a metal ion complexed to NH3, would Eriochrome likely replace NH3 via ligand ...
-2
votes
0answers
19 views

stability of cabergoline /dostinex [closed]

How stable is the following molecule, cabergoline? I'm wondering about the potency of expired medication (Dostinex) in which it is the active ingredient.
-1
votes
1answer
29 views

Formal Charges on Split Anions? [closed]

The carbonate anion $\ce{(CO3^2-)}$ Has 3 oxygen atoms with a total formal charge of $-2$. I was taught that formal charges had to be whole numbers. Even so, it appears each oxygen atom has a formal ...
1
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0answers
27 views

Why is L-lysine only sold as L-lysine HCl and not as base (cf. L-arginine)?

Both L-lysine and L-arginine enjoy popularity as supplements, but only the latter is sold either as HCl or as base. Given that L-arginine is even more basic than L-lysine (pH 12.5 vs 10.5), that is ...
0
votes
1answer
52 views

True muonium energy levels [closed]

In a true muniom(muon-antimuon atom) do the energy levels match with that of the hydrogen's? The core is lighter for about 100 times but the muon is 100 times heavier than the electron so it would ...
-1
votes
0answers
17 views

Assuming what is the freezing point of a solution of dibromobenzene, C6H4Br2, in 0.250 kg of benzene, if the solution boils at 83.5 °C? [closed]

Assuming ideal solution behavior, what is the freezing point of a solution of dibromobenzene, C6H4Br2, in 0.250 kg of benzene, if the solution boils at 83.5 °C? Benzene boiling point: 80.1 C Benzene ...
0
votes
0answers
16 views

Titration Determination of Ka [closed]

If 20.8 mLs of a 0.10 M solution of NaOH is needed to completely (100%) neutralize 10 mLs of a weak acid solution, how many mLs of the 0.10 M NaOH solution is needed to neutralize 50% of the weak acid ...
-1
votes
0answers
7 views

Stability of cabergoline [closed]

[![cabergoline ][1]][1] How stable is this molecule, the medication cabergoline? Wondering how safe it is past expiration.
-2
votes
0answers
14 views

Titration and Neutralization percentages [closed]

When one adds a 0.10 M NaOH solution to a weak acid solution, a portion of the weak acid solution is neutralized. If 20.8 mL of a 0.10 M solution of NaOH is needed to completely (100%) neutralize 10 ...
0
votes
2answers
69 views

Finding the pH of a solution [closed]

What are the steps we go about in finding the pH of a solution of Strong base and a salt of a Weak base and Strong acid? Here is the question that I've been given Find the pH of a solution made ...
-1
votes
1answer
30 views

Arsenic bound proteins confirmatory test

I want to confirm the presence of arsenic in some protein samples, apart from the marsh test can I use the following method?-- Arsenic is present as arsenic (III) ion in the samples. Hydrogen sulfide ...
5
votes
1answer
161 views

Why is 3,6-dimethylpiperazine-2,5-dione optically active in spite of having a centre of symmetry?

I learnt in my chemistry class that if a molecule has an element of symmetry (either a plane of symmetry or a centre of symmetry), it will not be chiral and hence will not show optical activity. My ...
-2
votes
2answers
57 views

Is it possible to remove dissolved chlorine from water? [closed]

So recently I was trying to disinfect water by adding bleach to it but accidently I added too much of bleaching powder. So now the water has a very pungent odour. Is it somehow possible to decrease ...
1
vote
0answers
22 views

How would you describe the energy of solution formation involved in the dissolution of sodium chloride in vinegar?

I have found that the lattice energy of dissolving salt in water is 779 kJ/mol. While 774 kJ/mol is its hydration energy. Subtracting the two values gives a positive number therefore dissolving table ...
0
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0answers
32 views

Will UVC harm smartphone's screen (especially OLED, AMOLED ones)? [closed]

I'm curious if UVC (with wavelength of 260-280nm) can in any way harm smartphones? There are this type of sanitizer products, like 59S S2, which are good for sanitizing small items, including ...
-3
votes
0answers
27 views

Temporary tattoo onto skin [closed]

I'm Martin I printed an image and I want to have it tattooed on my skin In your opinion, what material should I use to transfer the image to my skin? I had already seen a video on the internet about a ...
-1
votes
1answer
17 views

Does choline bitartrate react with hydrochloric acid?

Choline hydroxide is a base and reacts with HCl to form choline chloride salts and water. I am wondering if choline bitartrate can also neutralize HCl. In case it doesn't, is there any other cheap ...
1
vote
1answer
25 views

Non-toxic organic bases? [closed]

I am trying to find out if there are any non-toxic organic bases that could be given orally on a non-empty stomach to treat acidosis. From my research, histidine and diluted choline hydroxide were the ...
0
votes
1answer
19 views

Seeing solubility in various cases

[![enter image description here][1]][1] Question is in the image 'match' each option having multiple answers. I have invested a considerable time over this but couldn't solve it. Anyone explaining how ...
-1
votes
1answer
17 views

Steric Inhibition of Resonance effect on Dipole Moment

How does steric inhibition of resonance (S.I.R.) cause dipole moment of the compound to decrease? Dipole moment $\vec{\mu}$ is defined as $q \vec{l}$, where $l$ is the separation between the charges ...
1
vote
2answers
70 views

How the experimentally determine the elemental composition in fingernails?

I am doing a project in my highschool about analysing C/N and C/S ratio of finger nails of various ages and sexes. Please suggest me a way to do this. I don't know where to start, I know the various ...
1
vote
1answer
38 views

Why does covalent bonding satisfy atoms?

Having to retake an introductory chemistry course has gotten me thinking. Covalent bonding is where electrons are shared between two atoms that both want more electrons. Let us take $\ce{O2}$ as an ...
1
vote
1answer
37 views

Scale to be considered for comparing electronegativities of nitrogen and chlorine

The Pauling scale gives the $\chi$ values of $\ce{N}$ and $\ce{Cl}$ to be $3.04$ and $3.16,$ respectively, but the Allen scale gives the $\chi$ values of $\ce{N}$ and $\ce{Cl}$ to be $3.066$ and $2....
-2
votes
0answers
41 views

Question on Henry's law, Carbon dioxide in soda can [closed]

Solubility of CO2 at 20 degree Celsius and 1 atm is equivalent to 87.8 mL/ 100 mL water. Suppose the partial pressure of CO2 before opening a can of coke was 2.5 atm, calculate the molarity of CO2 in ...
2
votes
2answers
48 views

Chemicals that form coloured complexes with Pb2+

I’m currently conducting a photo-spectrometric analysis of lead concentration in water and was looking into using Eriochrome Black t as an indicator for Pb2+ (due to the complex forming a reddish ...
1
vote
1answer
55 views

Why is o-nitroaniline not more basic than aniline?

We know from SIR effect (Steric Inhibition of Resonance) that in o-nitroaniline, the nitrogen's p-orbitals will change their plane, causing the conjugation/resonance of its lone pairs to stop. So, the ...
0
votes
0answers
9 views

will K2co3 precipitate ca from a water solution [closed]

I have a KCl solution (20g/l)(2%?) with 500 mg/l of Calcium, I know the Ca can be precipitated with NaCO3 But can K2CO3 be used instead?
0
votes
0answers
20 views

What is the general or ideal equation for the radial wave function?

I came across this question on the internet: What is the value of $(n + l + r)$ in a given wave function, where $n =$ principle quantum number and $l =$ azimuthal quantum number and $r =$ total ...
2
votes
2answers
58 views

Writing half equation confusion [closed]

The following is the answer for a question that I am doing: Reduction: $\ce{X^2+(aq) + 2 e- -> X(s)}$ Can I write $\ce{X + 2 e- -> X^2-}?$ Why can't I start with $\ce{X}$ instead of $\ce{X^2+...
0
votes
1answer
24 views

Should I relate the number of moles between substances when converting weight units?

Good day! I graduated from an undergrad degree of chemistry almost 3 years ago but I'm frustrated that I fail to reconcile these things: In gravimetric analysis, to get the correct amount for the ...
0
votes
0answers
20 views

How does actually negative charge travel in phenol from ortho to para to ortho? [duplicate]

When we say negative charge flows from ortho to para position, and electron density at ortho and para is more, where does electron actually stay at ortho and para? Is it at $p_\mathrm{z}$ orbital or ...
-2
votes
0answers
22 views

We know that single bond,double bond structure of benzene doesn't exist then why we use it? [closed]

No explanation needed question is straight forward
0
votes
1answer
31 views

How to properly model a mechanochemical reaction of barium titanate and copper(II) complexes?

I would like to understand, in terms of chemical kinetics, how I could equate the reaction rate between $\ce{BaTiO3}$ and copper(II) complexes under ultrasound effect. Examples in literature would be ...
0
votes
0answers
17 views

Phase purity using XRD measurements [closed]

I want to know the XRD values in order to calculate the phase purity values of ABO3 perovskites, Is there a database of known XRD measurements or phase purities?
2
votes
1answer
31 views

Molecular antibonding orbitals energy

When we heat hydrogen the energy of the molecular orbital of H2(1s) is increased .What happens to the energy of the antibonding molecular energy of hydrogen(1s*)?

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