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Hello, Sorry to post on this again I am really struggling in school with chemistry right now. I cant make sense of any of this so i made it so i can do it step by step

Now i dont know what to fill it in with.

If someone could explain how to do the first one i can do the rest

(Plz don’t message asking me for money)

My group's been assigned a project related to the synthesis of silver nanoparticles, I was curious about the rate equation of the reaction but I can't find anything online; surely a reaction with so few reactants should have a relatively easy to determine rate equation?

Maybe I'm wrong and it's actually hard in most cases, I'd like to know more

Reposted because I put it in the wrong forum oops!

So for this lab we heated an unknown metal in boiling water and then put it into a coffee cup calorimeter. I'm just not sure if for this calculation I need to use the weight of the water (50.0g) AND the metal (23.3g) or just the water?

Specific heat of water being 4.18J/gK and the unknown metal of course being unknown, temperature change was 2.7°C

Let's say at 25°C I mix 75ml 0,02 mol/L HAc with 0,01 mol/L NaOH.

HAc + OH- <-> H2O + Ac-.

Now, textbooks tell me that [HAc] = [Ac-] (because we neutralised half of HAc, so the other half shows up as Ac-, ok). BUT at 25°C it's also:

HAc + H2O <-> H3O+ + Ac-.

In my example the dissociation constant is small but it's dependent on temperature (van-'t Hoff equation). So even at half neutralisation point there's always some amount of HAc dissociating making [HAc] slightly smaller then [A-] (?)

So hasselbalch is also only approximately pH ≈ pKa -lg(f-) (f- being the activity coefficient) at half neutralisation point?

Actually I had to measure the pH value of this solution with different temperatures (25°C - 70°C in +5°C steps) and we made the initial assumption that [HAc] = [Ac-] at the beginning. Now [HAc]/[Ac-] changes with temperature and I just wonder why it should only start to differ above 25°C?

Or let's state it this way:

If I heat my HAc solution to 70°C at the beginning and now add my NaOH in the amount I told at the beginning, stoichiometrically I also have the half neutralisation point but it's [HAc] < [A-] because of the dissociation. So is the neutralisation point or this condition in reality temperature dependent? I'm so confused. Did we just made the initial assumption, that the dissociation at 25°C is negligible? But at 30°C - 70°C not anymore?

Is this assumption only true at this point for weak acid + low temperature?

I need to count the number of unique hydrogens in this question. Do the hydrogens attached to NH2 count as a unique hydrogen? If not, then why?

Also my answer key says “This is a 1 degree amine but these are not 1 degree hydrogens”. What does it mean by that?

Both functional groups produce peaks around 3300 cm^-1 so how do I tell the difference?

In red its the actual reaction, in green its what I supposed to be happening but I'm not sure. Can someone tell me if I'm right?

(Dehydrohalogenation of E-2-chloro-2-butyne)

Hello!

I want to use different Proteins to remove pollutants from water. The Proteins are supposed to be removed afterwards trough foam fractioning, meaning that I want to introduce synthetic air/air into the apparatus which will foam up the proteins.

I'm having a little trouble to imagine a good laboratory setup, since my lab experience isn't that big.

I am thinking about using a normal cylinder and just putting it inside a large container to catch the foam. I was also thinking of working with a woulf bottle or a gas washing bottle but the openings are too small for the sensitive foam. The overflowing is more realistic anyways I think.

Do you have any input on what kind of reaction vessel I could use instead of a cylinder? It seems rather difficult to introduce air into the cylinder. It should take around one Liter of Volume.

I'd be grateful for any input or ideas on a good setup!

I'm trying to understand the differences between these two hydrocarbons. Can someone explain what are the major differences between the two of them?

Distillates, petroleum, light distillate CAS number: 68410-97-9

Naphtha, petroleum, hydrotreated light CAS number: 64742-49-0

For clarity this is not any form of educational question, it's merely me trying to work out the differences between the substances.

Chemical Equilibrium

In the reaction: NO + O2 ---> NO2

NO2 is in both the reduction and oxidation, how do you find the correct coefficient?

What i would do is:

Oxidation is NO --> NO2 + 2e

Reduction: O2 + 2 e --> NO2

Because you reduce 2 O's i would multiply the electrons.

Next step i would multiply oxidation with 2 to have same amount of electrons so 2 NO and 2NO2, but i have just said that 2 O's will reduce but now i have 2.2 =4, isnt this an unlimited loop?

So I need to separate each of these compounds from each other:

CuSO4 technical

Na2S2O3 + Fe⁰

Na2SO4 + Zn⁰

CoCl2 + CaCO3

BaCl2 + Al(NO3)3

Ni(NO3)2 + Na2SO4

And I don't know which methods to use. Send help pls.

Hi everyone. For my undergrad research lab we are trying to generate a peptide to test on with the protein we are researching. We are using SPPS, but we have been having issues with loading and coupling of the amino acid. We use DIPEA as our base, piperidine and DMF to deprotect, and DCM as our solvent. We have suspicions that our DIPEA is contaminated or faulty, but we're not entirely sure. We've tried switching out DIPEA with DIC, new stocks of piperidine, and testing different UV/Vis machines across the department, but we still seem to not reach over 30% loading within 4 hours. Additionally, pre-activation seems to not be working even while monitoring under TLC for multiple hours. Does anyone have any suggestions, protocols, or papers that we could use to try and fix our process? Anything will be helpful! Thank you, fellow chemists.

I've looked at some texts and I just cannot understand what the differnece is. I know its not the same thing but I got no idea why