I know that in octahedral complexes, d-d transitions are Laporte forbiden since they involve g-g transitions, and so the ε values for these transitions are very low. However, in square pyramidal complexes, there exists no such centre of inversion, so would d-d transitions become no longer Laporte forbidden, and have higher ε values - perhaps on the order of 10³ dm³/mol/cm?

https://preview.redd.it/3mgsobwj0r4e1.png?width=737&format=png&auto=webp&s=c77aa3287fa2487739768595f6f9f3fa1262d791

Would I draw it interacting with the Na ion? It asks for just one but isn't there multiple places it could go

Is F higher in energy than E because it’s kicking out a bad LG (methyl)?

I counted 4 but the answer key says 6, what am I missing?

https://preview.redd.it/uv0efbuelq4e1.png?width=799&format=png&auto=webp&s=317b9006d019bff6807c3fd77bb80a951c98b9da

Im not asking for answers but I cannot decide the final structure of the molecule. I believe its a naphthalene derivative with 2 methyl groups such as 2,6-dimethyl naphthalene but cannot decide where on the location of the methyl groups. I also dont understand the triplet in the H NMR and where that comes from. Can anyone give me any ideas/ topics to read to help understand?

Hi, I am 19 years old and trying to complete my CREST Award relating to computational chemistry and modelling etc. (for University - I took a gap year and am no longer in college so have no teachers to ask for help). However, I tried downloading some free software on my MacBook and I am really struggling with it and I can't seem to find any help anywhere. If anyone has any good suggestions on free software I can download and use for my project (I can't do it without) and can help me with fully downloading it to my laptop I would be unbelievably grateful. Thank you so much <3.

I posted this on either here or r/chemistry and was not allowed apparently, however someone commented on it and I took a glance and was going to read and reply later but when I came back the comment had gone (I believe the moderators removed it - but they were so helpful and I didn't even get their username to privately message them :(

Given reactions:

A --> 2B, 0th order, k_0

B --> C + 2D, 1st order, k_1

Derive integrated rate law for concentration of A, B, C, D at any time t. Given that initial concentrations of A = A_0, B = C = D = 0.

I tried deriving for A_t, I got A_t = A_0e^(-k_0t) like normal zeroth order reaction but for B_t, I got a graph that does not have a maxima and does not decrease after A_0 is depleted. How to derive equation for B at any time t? thank you.

Here's my work:

https://preview.redd.it/4fqif9lkgq4e1.jpg?width=2360&format=pjpg&auto=webp&s=a043aba2477005b8453ab35dc582899a0d9c32cd

red line is A_t

blue line is B_t

All I know that this isn't a cyclopentane because the Nitrogen doesn't complete the cyclo.

I'm trying to dissolve finasteride powder in 70% alcohol. But the finasteride goes into a white precipitate. I see precipitate at the bottom.

Do I need more concentrated alcohol?

please give me advice.

Hi everyone, i probably have to do a Fractional Distillation with reduced pressure tomorrow. Bit embarrassing but anywhere in the lab i absolutely suck at actually getting a decent pressure down…

Any tips or tricks y‘all use to get a decent vacuum?

I usually use a membrane pump

If anyone is able to help me it would be greatly appreciated. My work is in blue, answer key is red.

For the first one: I'm not sure how the chain with the epoxide from the answer key ended up looking like that.. is my step one product correct? If so, how does the epoxide not form as I have drawn it?

For the second: From my understanding, the first step would go through a chloronium ion intermediate and then the water would attack the more substituted centre, leading to trans-oriented Cl and OH, right? And then in the second step, it would be an SN2 attack of the Cl, resulting in cis-oriented OH groups?

What is an alternative to MIRVASO (brimonidine) that could work permanently in removing skin redness?

So I'm a college freshmen majoring in chemistry and I've never struggled with chemistry or studying before. However, as the semester is rolling by my exams scores are getting worse. I do well on lab work and homework, (ex. high 80's low 90's) but on exams, especially the multiple choice section, I'm absolutely bombing it. What do I do and do you guys have any studying tips/techniques?

Just did a titration lab to determine the ksp value of Ca(OH)2 using HCl, I listed all of the info on the left. The accepted value is 5.5×10^-6 but I got 2.37×10^-5, can anyone check my calculations? Thanks

Hi, I am 19 years old and trying to complete my CREST Award relating to computational chemistry and modelling etc. (for University - I took a gap year and am no longer in college so have no teachers to ask for help). However, I tried downloading some free software on my MacBook and I am really struggling with it and I can't seem to find any help anywhere. If anyone has any good suggestions on free software I can download and use for my project (I can't do it without) and can help me with fully downloading it to my laptop I would be unbelievably grateful. Thank you so much <3

The carboxylic acid somehow hinders the reaction? How?

I understand how to identify each one but I'm confused on when exactly I use them?

My understanding was that you use cis/trans when there is clear stereochem show (dashes/wedges) and when you have a same group on the Cs on either side of a double bond (i.e. RHC=CHR' --> H being the same group)

E/Z is used when you have all different groups on each C (i.e. RXC=CHR')

r/S I thought was used mainly in chiral centers?? Not sure if this is correct.

For example (from my textbook; sorry I don't know how to do the subscript 😭 ):

cis-1-bromo-9-octadecene --------[CH3(CH2)4]2CuLi-------> 9Z-tricosene

Why I'm confused with this particular example:

How can Z designation be used when there are Hs on both the Cs on either side of the double bond?

Also, the book does not show dashes/wedges when drawing cis-1-bromo-9-octadecene so how can it be cis???

https://preview.redd.it/656smrrpvn4e1.png?width=1033&format=png&auto=webp&s=c4365b5934c8a87610feb76a6eb432fc409a252b

According to the paper that this image is from (https://doi.org/10.1016/j.tetlet.2014.02.065) the reaction to 5 only really works (at least with decent yield) when water is added. The authors argue, that water forces pathway b) to occur instead of pathway a). Me and my supervising phd student are a bit confused by this. Shouldnt the imine carbon be electrophilic enough for pathway a), especially once compound 4 is irreversibly oxidized?

Hi, everyone, I'm trying to understand how a reaction of acid/base will work to clear a clogged drain. I'm well out of school and have only a very basic (heh) understanding of chemical reactions, so please be gentle.

In a nutshell, people are suggesting a mixture of vinegar and baking soda to clear a clogged drain. My understanding is that mixing these two substances creates a bunch of CO2, but that the acid and the base basically neutralize each other. (I'm probably wrong about that.) So, how does that mixture work to unclog the drain?

So, I want to make NaOH, but I don't have access to electrolysis, any kind of lime, nor high temperatures (max 200 C) My chemicals are normal kitchen stuff, Na3PO4, CuSO4, MgSO4, Citric acid, K2S2O5, Na2CO3 and NaHCO3. Is it possible?

We are design students and desperate—we need to design a heating patch for the face. We took inspiration from heating patches for the back. Can any chemist tell us if significantly reducing the size of the "pouch" containing the salt, charcoal, etc. mixture affects the temperature reached and/or the duration of the effect

I need your help on the IUPAC idk if i understand the rules of priorities and everything can you tell of you name this organic compounds and why

https://preview.redd.it/n3h77gq1gn4e1.jpg?width=3060&format=pjpg&auto=webp&s=ab696e7f778dc7ce82cb991cb2a0d6556bb97bfe

I’m really struggling with how to convert 18PgC to CO2 ppmv. Any help would be greatly appreciated. :)

can a kind soul help to explain this thankyou somuchhh

Why is this Diels Alder reaction considered acid base? Isnt the transfer of electrons cyclic, so just as butadiene transfers electrons to ethene, ethene also transfers electrons to butadiene? If so then how would you determine which is acid and which is base? The orange ink and pencil marks is drawn by me, not sure if the movement of electrons is correct

Can someone please provide the name of the reaction or type or help with a source describing a similar mechanism?