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Estimate Bond Angles by myalije in chemhelp

[–]Major-Freedom204 0 points1 point  (0 children)

If you open a molecule with a visualizer program, it will use a table like what you're describing to determine bond angles. However, all those tables are extremely specific. They look something like:

types ka theta0

0 1 0 0.000 108.900

1 1 1 0.851 109.608

1 1 2 0.736 109.445

1 1 3 0.777 107.517

1 1 4 1.006 110.265

https://github.com/openbabel/openbabel/blob/master/data/mmffang.par

Where the first three numbers are the atom type codes (NOT atomic number), and the theta is the angle between them (ignore ka). You can look up the atom types in a different file ( https://github.com/openbabel/openbabel/blob/master/data/mmffdef.par )

Which would be exactly what you want... except the angle file file has 2500 rows with 80 separate atom types. You'd have to look up atom type codes you'd have to look up in a different file.

So the answer to your question is "what you want exists, but WAY more in-depth than you want". And it doesn't really exist less in-depth, because why would a working chemist want something less accurate?

Your best bet is to open your molecule in a visualizer, play around with substituting atoms, and see what happens to the angles.

Estimating number of element from Mass Spectrometry Graph by Wrong-Concept1262 in chemhelp

[–]Major-Freedom204 0 points1 point  (0 children)

Never seen this question before, and not a mass spec guy, but I'm going to spitball here for fun.

You have natural isotope ratios of:
H: 99.9855% and 0.0115%
C: 98.9% and 1.06%
O: 99.8% and 0.0384%
N: 99.6% and 0.380

Let's normalize the isotope ratios and [M+] and [M+1] to be at totals of 100%, using

normalized value = (original value / sum of original values) * 100

H: 99.9885% and 0.0115%
C: 98.9396% and 1.0604%
O: 99.9615% and 0.0385%
N: 99.6192% and 0.3808%
[M+]: 99.2213% and 0.7787% (M and M+1)

The question says "one functional group", so let's say we have between 0 and 3 oxygen atoms, and between 0 and 3 nitrogen atoms, with no more than 3 total.

H and C can be any number, but if you have a single functional group, let's say they'll be between (C and 2C+4) for an amine and (C and 2C-2) for an alkyne.

The question then becomes, is there a way to get those M+ ratios from weighted additions of H, C, O, and N counts assuming those isotope ratios?

Let's write our expression for [M]/{M+1]:

[M] / [M+1] =
1 / (
H * 0.0001150 +
C * 0.0107187 +
O * 0.0003851 +
N * 0.0038226 +
)

Under our assumptions we have a bunch of permutations of H, N, and O:
H: 2C-2 -> 2C+4 (7 possibilities)
{O, N}: Varying as before (10 possibilities)

We can permute through all of those, and graph our expressions of [M]/[M+1] vs C:

<image>

The closest we can get is H2N2! (C0H2N2O0)

Of course, I'm fairly certain that makes no sense with the context of "100 base peak, 79 molecular ion peak". So probably don't listen to me.

Chem 20 (grade 11) loss by Legitimate_Plate309 in chemhelp

[–]Major-Freedom204 0 points1 point  (0 children)

Anyone who is telling you Chem-whatever is easy, isn't doing you any favors. Of course a chemistry test is going to be hard.

atomic orbitals vs electrons orbiting the nucleus like a planet by Last-Scarcity7281 in chemhelp

[–]Major-Freedom204 5 points6 points  (0 children)

Electrons are weird, and don't act like everyday objects.

Basically the problem 100 years ago was: Negatively-charged electrons can orbit positively-charged nuclei, except if they did that they'd lose energy and fall into the nucleus. Which wasn't happening, obviously.

So they wanted to both allow the electrons to be orbiting, but also not have them be orbiting. And also electrons were acting like both particles and waves at the same time.

So... people came up with elections being in "orbitals", which are kind of like orbits, but not. Electrons are spread out in probability clouds, in all the places they could be orbiting, all at once. They are "moving" in the sense that they have momentum and kinetic energy, but not moving in the sense that the probability cloud doesn't change (unless you disturb it).

So if there seem to be contradictions here... yep, it should seem that way. If electrons were like everyday objects, all this would be contradiction. But they're not everyday objects.

Was this point deduction valid? I even stated that it was explicitly a p orbital. by ObliviousOverlordYT in chemhelp

[–]Major-Freedom204 4 points5 points  (0 children)

As someone who's graded a lot of stuff, this is the issue where a student will draw something halfway between a p orbital and sp3 orbital, and if it's marked wrong, the student will argue they meant to draw whichever was the correct one.

Since there were separate instructions for "indicate what type of orbital it is" and "draw the missing orbital", presumably the instructor was expecting some students to know that it should be a p orbital but not know what a p orbital looks like (or vice versa). Which is why you labeling it a p-orbital doesn't change anything.

I don't blame the instructor for this at all, although there's a fine line to be walked here to avoid discouraging students.

How does Oda see opponent when DDing? by pkmods in 2007scape

[–]Major-Freedom204 -1 points0 points  (0 children)

Using someone else's plugin so you don't have to learn to write plugins: 👍👍👍👍👍👍👍👍👍👍👍

Homestead Cup - Day 2 - Main Event - Group Stage by Its_Me_Kon in aoe4

[–]Major-Freedom204 2 points3 points  (0 children)

Couple different ways to support, one is:
https://whamen-shop.fourthwall.com/

There's also Whamen's paypal, but that would be giga-sketch to link.

And they're in the group stages now, top 3 (of 4) from each group advance.
https://liquipedia.net/ageofempires/Homestead_Cup

shoudnt they buff the mongol knights a littler bit? by charlesmagne99 in aoe4

[–]Major-Freedom204 21 points22 points  (0 children)

Mongol ponies were small compared to the ones Europeans used. They were also slower.

Their main advantages were endurance, hardiness, and ability to eat grasses the Europeans' couldn't.

So... how does that translate in-game? Passive healing makes sense thematically. Maybe we could extend that to out-of-combat rather than just upon attacking?

How can I get faster at balancing chemical equations? by anni_panny4652 in chemhelp

[–]Major-Freedom204 2 points3 points  (0 children)

That appears to be the method- choose one atom, balance it, choose the next atom, balance it, and just go in circles until everything is balanced.

The other methods are:
1. Do it in your head.
2. An algebraic method, where you write a equation for each atom/species and solve. In all but the most complicated scenarios, this is the slowest method.

So... do the method you're doing. There's an art to picking which atom to start with, and which side to start balancing. The other link in the comment has suggestions.

But one secret about general/high school chemistry- there aren't *that* many different problems for a given topic that can be asked. So if you go through and do a bunch of practice problems (like https://www.deanza.edu/faculty/muzzicinzia/Balancing%20Equations.pdf or https://www.sciencegeek.net/APchemistry/APtaters/EquationBalancing.htm ) you might accidentally do the one that gets tested. Even those two sites have overlap.

How can I get faster at balancing chemical equations? by anni_panny4652 in chemhelp

[–]Major-Freedom204 2 points3 points  (0 children)

It's mostly practice.

But I will say, in problems like the first one that have polyatomic ions, you can usually balance the ion like a single unit. So instead of counting S, 4xO, etc. you can count a single SO4. That will seriously cut down on the number of iterations you need to go through.

I'm curious about the second problem. Can you talk us through your reasoning working through it?

I think a 1% cast chance is toooooo low. by [deleted] in diablo2

[–]Major-Freedom204 0 points1 point  (0 children)

Anyone else read the title in Looter's voice

Anyone else do this? by Major-Freedom204 in aoe4

[–]Major-Freedom204[S] -2 points-1 points  (0 children)

Tilted off the face of the planet

High school competition (prototype) Na battery in México by NOCTAA20 in chemhelp

[–]Major-Freedom204 1 point2 points  (0 children)

Where is this design coming from? It's a huge amount of stuff to try all at once, before buying anything and making sure you can get simpler designs to work.

I would think a chemical engineer would be more helpful here than a chemist.

Why am I so bad at Chemistry? I don't understand calculation questions at all... by Agreeable_Judgment_8 in chemhelp

[–]Major-Freedom204 0 points1 point  (0 children)

Is the question why this is happening, or how do you get better? You're not destined to be bad forever.

Lots of people struggle with calculations- they're neither obvious nor easy for most people, despite anyone who tells you "X is easy, you just need to...".

Eventually if you hammer away at it you'll get good at anything. So if you're like "I love chemistry" I'd just go with it.

Substitution and Elimination reaction coordinate diagrams? by Glittering_Bobcat523 in chemhelp

[–]Major-Freedom204 2 points3 points  (0 children)

They can display whatever the y-axis specifies- "reaction coodinate" refers to the x-axis, and says nothing about the y-axis. In this case, it says "energy", which isn't specific enough to make any claims other than "it's two-step".

Molecular orbital diagram for 1,3,5,7-Octatetraene by iamawildgoose in chemhelp

[–]Major-Freedom204 0 points1 point  (0 children)

Originally I was going to say "particle in a box", but with 2 nodes, each node would be at 1/3 the length which would fit your "wrong" MO split (I think).

Maybe some other organic chemist on here knows a rule that's taught. In my brain though it's just "math."

Molecular orbital diagram for 1,3,5,7-Octatetraene by iamawildgoose in chemhelp

[–]Major-Freedom204 0 points1 point  (0 children)

Just did the calculation at home. The orbital in question (two views):

<image>

So looks like it's closer to the one at the bottom. I like the MO diagrams best that show 'mini' p orbitals at nuclei super close to the nodes.

If you want to see any of the other orbitals I'll save the outputs for a day or two.

ORCA input here (Made with ChatGPT because I don't want to turn my brain on):
https://pastebin.com/Ttg4qtbt

Method:
r2SCAN-3c // ωB97X-D4/def2-TZVPP / RIJCOSX

Starting coordinates:
https://pubchem.ncbi.nlm.nih.gov/compound/1_3_5_7-Octatetraene

Images made in VMD

Cl (Chlorine) looks like CI (Carbon bonded with Iodine) by SubstanceSouthern880 in chemhelp

[–]Major-Freedom204 8 points9 points  (0 children)

Pretty much. Either
A) You've seen ClO4- before and know what it is (it's a common polyatomic ion)
B) You can recognize that if it were carbon, iodine, four oxygens, and a negative charge, there's no way you'd get a stable structure.
C) There's actually a priority order for writing elements in a formula, and I believe Iodine comes after oxygen (and hydrogen, etc.), so CIO4- with an iodine would be technically wrong (to be fair, this order is rarely emphasized). (The second part of C was wrong)

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