The h Bar

@DanielSank Well, yes - you can sure say "I think you shouldn't flood the star board with trivial messages because it makes it useless" but that neither removes the stars already cast nor ensures it doesn't happen again in any way.

It's not really an alternative to cancelling the stars because it doesn't fix anything.

Yashas Samaga

Hydroxylamine isn't organic, so I'd rule out NO2

John Rennie

6:03 PM

Seven planets!

anonymous

Okay! I was right. Answer is N2O! :)

ACuriousMind

Just like explaining to people that they shouldn't use sockpuppets to upvote themselves is not a replacement for deleting the socks, to extend your parallel to voting.

John Rennie

Three in the habitable zone!

anonymous

chemiday.com/en/reaction/3-1-0-13066

user228700

@JohnRennie Haven't u been awake for awhile now? The Google doodle has been up since morning...

DanielSank

6:04 PM

@ACuriousMind It's not an alternative to removing stars, no.

Yashas Samaga

You'll always get chem answers in the exam

DanielSank

It is a way forward.

Yashas Samaga

@anonymous half of the options will have unbalanced charge/oxidation number

John Rennie

@Kaumudi.H I don't waste my time surfing the Internet :-)

Yashas Samaga

@anonymous you can easily eliminate a few

John Rennie

6:05 PM

(I waste it talking about food here :-)

anonymous

@YashasSamaga What is the product when NaNO3 is very strongly heated?

user228700

@JohnRennie Lol, suuure x'D Nope, this guy only scours the internet for shiny and cute laptops to buy every so often!

0celo7

@ACuriousMind homology of boundaries

Yashas Samaga

@anonymous O2, NO2, Na2O?

or it just gets reduced to NaNO2 and O2

ACuriousMind

@0celo7 Well, I currently have no new idea, so I have nothing to discuss :P

Yashas Samaga

6:07 PM

@anonymous I'd guess if the options were there

anonymous

@YashasSamaga No.

John Rennie

@Kaumudi.H I buy PCs too! In fact I bought one yesterday (for my aunt-in-law).

0celo7

@ACuriousMind Lee has the one and two dimensional cases separately. I'll try to do those

Yashas Samaga

@anonymous If those two are wrong,t hen the only answer remaining is Na2O and NO2

anonymous

@YashasSamaga If you need options to answer a question then you haven't learnt Chemistry.

0celo7

6:08 PM

@ACuriousMind (I am caring about topological manifolds all of a sudden because we are doing them in alg. Top)

anonymous

@YashasSamaga Still wrong.

Yashas Samaga

@anonymous I need options for block chem questions

user228700

@JohnRennie Yes of course, PCs too, how dare I forget about them?! :-) When are u going to fix it for her?

anonymous

@YashasSamaga What will you do if such questions are asked in Integer type?

Yashas Samaga

@anonymous whats the answer?

John Rennie

6:09 PM

@Kaumudi.H Weekend after next. That's the first weekend I can get away.

Yashas Samaga

@anonymous I will be revising block chem a week before JEE

anonymous

@YashasSamaga Hint: NO2 can't be formed in such a reaction.

user228700

@JohnRennie Cool :-)

Yashas Samaga

@anonymous What?

@anonymous Pb(NO3)2 gives NO2, PbO, O2

AccidentalFourierTransform

DanielSank

6:09 PM

@JohnRennie "in-law"!

Yashas Samaga

@anonymous I can give countless reactions where you get NO2

DanielSank

I thought you were unwed.

anonymous

@YashasSamaga s(I) block elements are special.

Yashas Samaga

AHA! John Rennie is married!

anonymous

think why.

0celo7

6:10 PM

@DanielSank his brother's in-law

user228700

^

John Rennie

@Kaumudi.H I might give her a wireless router as well. My niece is always complaining there's no wifi at granny's house.

DanielSank

ah

John Rennie

@DanielSank Brother's mother in law

user228700

@JohnRennie Aww <3 :-)

0celo7

6:11 PM

@JohnRennie I already said that >:(

John Rennie

Sorry, I've been working for 13 hours and the brain is on the fritz.

whatin1992

Should I ask my question as a full-fledged question on the site?

John Rennie

@whatin1992 what's the question?

anonymous

John Rennie is enjoying a happy polygamous life with his laptops :D @DanielSank

Mostafa

@JohnRennie Maybe you should post a question We seem to be over-eager to star in meta.

46

Q: We seem to be over-eager to downvote

Take this question: Dark matter clumping This is an excellent question and the answer is not at all obvious. I assume it was downvoted just because it's a duplicate, but is this really appropriate? Downvoting can be used to make questions disappear from the home page, and also to deter people f...

whatin1992

6:12 PM

@JohnRennie Why is it that a system can be entirely "described" by its Hamiltonian? I see the Hamiltonian as only an operator. Isn't the wave function the true way to fully describe a system?

AccidentalFourierTransform

wawe-functions

ACuriousMind

@whatin1992 The wave function describes the state of the system, the Hamiltonian its time evolution.

anonymous

@YashasSamaga Did you understand why s(I) block doesn't produce NO2?

Yashas Samaga

@anonymous I did not check yet. Tell me why.

user228700

6:14 PM

@AccidentalFourierTransform ^

whatin1992

@JohnRennie right, but I was curious about the wording in my book. They say this multiple times "a system described by the Hamiltonian $H$..."

AccidentalFourierTransform

@Kaumudi.H lol, who's the guy? he sounds familiar for some reason

John Rennie

@whatin1992 the Hamiltonian gives you the eigenfunctions, but the initial state of the system can be any linear combination of the eigenfunctions. The Hamiltonian then tells you how that state will evolve with time.

user228700

@AccidentalFourierTransform He is the infamous John Green :-)

ACuriousMind

@whatin1992 Don't overanalyse the language, it's rarely worth it. The Hamiltonian "describes" the system in the sense that given an initial state, you can predict the future state with it.

anonymous

6:15 PM

@YashasSamaga One reason is their very high stability. Now think why they are highly stable. Their e.c. and electronegativity plays an important role.

Yashas Samaga

@anonymous stablity of?

anonymous

@YashasSamaga Nitrates.

whatin1992

@ACuriousMind that's my biggest problem :( I should have been a mathematician...

Yashas Samaga

@anonymous somewhere earlier I had told NaNO2 + O2 too

AccidentalFourierTransform

@Kaumudi.H and... why the paint? lol

anonymous

6:17 PM

@YashasSamaga That happens on mild heating

user228700

@AccidentalFourierTransform "Sharpie face" is a thing :-P Here:

user228700

nerdfighteria.info/v/YU4XXsAHplI

anonymous

@YashasSamaga Next question: NH2OH + H2O2 = ?

Yashas Samaga

It oxidizes, hmm.

anonymous

To what?

AccidentalFourierTransform

6:19 PM

@Kaumudi.H oh well, I was expecting something like "his two-year-old daughter" or something :-P

Yashas Samaga

@anonymous thinking...

@anonymous I have seen that combination in organic chem

@anonymous not sure where

@anonymous I am trying to recall that reaction and its mechanism

AccidentalFourierTransform

@whatin1992 You're now officially a physicist. Congratulations!

whatin1992

@AccidentalFourierTransform please halp.

send cookies :)

user228700

@AccidentalFourierTransform Interestingly, he does have a 2 year-old daughter :-) Anyhoo...

ACuriousMind

@AccidentalFourierTransform Saying one should have been a mathematician is the hallmark of a physicist?

Yashas Samaga

6:21 PM

@anonymous I am not sure. What's the answer?

whatin1992

Did anyone here feel like their undergrad career was mostly frustrating? I'm in the U.S. and my undergrad studies don't make me feel like I'm really understanding the physics behind it all.

anonymous

@YashasSamaga A blue liquid.....

whatin1992

It just feels like I'm learning the top layer of something and before I can go deeper into it I'm rushed off to learn the top layer of something else.

Yashas Samaga

@anonymous NH3? =.=

nvm

anonymous

@YashasSamaga No.

Yashas Samaga

6:22 PM

reduction gives NH3

AccidentalFourierTransform

@ACuriousMind of course. As soon as we realise we are not getting a real job anyway, we all regret not studying mathematics :-P

anonymous

NH3 is blue ! OMG XD

0celo7

@ACuriousMind I have the one-dimensional case.

Yashas Samaga

@anonymous it's yellow

@anonymous I got confused

anonymous

It is a nitrogen oxide

0celo7

6:23 PM

It's the old "remove a point from a line"

Yashas Samaga

@anonymous nitrogen which oxide?

John Rennie

@whatin1992 a physics degree has to cover such a wide range that it inevitably can't go too deeply into any particular subject. That doesn't stop you reading up anything that particularly interests you, or even asking about it here.

AccidentalFourierTransform

I need help with my math :-(

Yashas Samaga

@anonymous H2O2 is a weak oxidizing agent?

anonymous

@YashasSamaga A nitrogen oxide whose color is blue in liquid state. Finding it out is your homework. Seriously revise your inorganic!

Yashas Samaga

6:24 PM

@anonymous In ozonolysis, we use it as a strong oxidizing agent, right?

anonymous

@YashasSamaga It can be either oxidizer and reducer depending on the substrate.

whatin1992

@JohnRennie totes.

AccidentalFourierTransform

does $$\int\mathrm d^3x\ |f(x)|^2<\infty\quad\Rightarrow\quad|f(x)|\sim |x|^{-2}$$, right?

Yashas Samaga

@anonymous ... yes it is but you use it as a strong oxidizer in ozonolysis?

@anonymous if u use a super strong oxidizing agent, u'd get N2

anonymous

@YashasSamaga Its not very strong compared to say K2Cr2O7 or KMnO4

whatin1992

6:26 PM

@AccidentalFourierTransform don't scare me!! I'm convinced that with my skills I can get a job anywhere in tech. Do you agree? I think I should be fine because they're not only teaching us to be physicists but also part mathematicians and programmers

Yashas Samaga

@anonymous well, it breaks the double bonds in ozonolysis

@anonymous milder oxidizers such as SRR, PCC, ColR don't

AccidentalFourierTransform

@whatin1992 will you take me with you? I want a job too :-(

anonymous

It is a medium range oxidizer

whatin1992

@AccidentalFourierTransform omg you're scaring me. Now I feel like I should have gone to the career fair today...

0celo7

@AccidentalFourierTransform I can help with math - algebraic topology

whatin1992

6:29 PM

I just want to get an A in my QM class and also in my EM class :/ my undergrad career would feel complete if I did...

AccidentalFourierTransform

I want to be rich just like my dad

he is not rich, but he also wants to

whatin1992

@AccidentalFourierTransform I chose physics but I have a knack for business. I plan on starting a few of my business ideas after I finish

@AccidentalFourierTransform LOL I get it

twas funneh

AccidentalFourierTransform

@whatin1992 oh well, good luck with that :-)

and, if you ever succeed, remember who encouraged you

and hire me and give me loads of moneys

Koolman

@YashasSamaga can you help me in that

AccidentalFourierTransform

@0celo7 I need help with $x^2+1=0$

0celo7

6:33 PM

@ACuriousMind There should be an alternative proof via the invariance of domain theorem.

@AccidentalFourierTransform algebraic geometry is also something I can't help with

AccidentalFourierTransform

is it $x=i$ or $x=-i$? or is $i=-i$?

anonymous

@AccidentalFourierTransform Start astrology as a side job. If you can fool people well you can even become a millionaire. :D

0celo7

@AccidentalFourierTransform both

Yashas Samaga

@Koolman I forgot how those expressions are written

AccidentalFourierTransform

@anonymous tbh, I like astrologists better than astrophysicists.

Koolman

6:35 PM

Anyone else help me in that

anonymous

@Koolman It is just a double OR with a connecting AND

0celo7

@AccidentalFourierTransform ???

anonymous

That is one of the simplest questions you will ever find in your paper ;')

@Koolman

AccidentalFourierTransform

I dont trust astrophysicists

and cosmologists

0celo7

Why?

Racism I bet

Koolman

6:37 PM

@anonymous That I know , but now how to find output

anonymous

@AccidentalFourierTransform Yeah, I like them too. They know how to earn money without any struggle, unlike astrophysicists :P

skullpetrol

(removed)

anonymous

@Koolman (A OR B) AND (A OR C).

Koolman

@anonymous how ???

anonymous

@Koolman Read up some examples from ncert. It is given clearly man!

0celo7

6:39 PM

My avatar is pretty great right now

Watch this :

What is it? @0celo7

@ACuriousMind inclusion induces a _____ on fundamental group

Injection?

anonymous

@YashasSamaga Which metal hydroxides can dissolve in excess ammonia solution?

ACuriousMind

@0celo7 No, consider $S^1 \to S^2$

0celo7

6:43 PM

Dammit

This problem is too hard

skullpetrol

Have you seen the Chembot in action? @ACuriousMind

AccidentalFourierTransform

what is the rank of the homogeneous Lorentz Group? two, right?

and what are the Casimir operators? one is $J_{\mu\nu}J^{\mu\nu}$, but what is the other one?

0celo7

@ACuriousMind I have a proof for two dimensions. Would you like to hear my proofs? Maybe it will inspire you

@AccidentalFourierTransform rank?

AccidentalFourierTransform

@0celo7 yes, the dimension of the Cartan subgroup

0celo7

Oh god

AccidentalFourierTransform

6:50 PM

in general, equal to the number of Casimirs

0celo7

Not you too

AccidentalFourierTransform

I... what?

ACuriousMind

@skullpetrol no

@0celo7 You can write them down here, but I'm cooking for the next twenty minutes or so

0celo7

@ACuriousMind Ok. One is wrong anyway.

Koolman

@anonymous we can solve that when a,b,c are numbers and drawing truth table

0celo7

6:52 PM

Fundamental group is so counterintuitive.

skullpetrol

Would you be opposed to putting a fork in here? @ACuriousMind

anonymous

@Koolman Why use truth table when you can use Boolean Algebra.....

Koolman

But here they re represented by A , B ,C @anonymous

anonymous

I hate writing out truth tables anyway

0celo7

@anonymous @Koolman @YashasSamaga Can JEE people please make a separate chat?

3

anonymous

6:53 PM

@0celo7 No, I like this room. Feel free to click on ignore.

0celo7

@anonymous Fine.

I can't ignore on mobile.

Koolman

@anonymous truth table

anonymous

We are talking about Physics anyway. I don't see the problem. Even when you and ACM talk I get distracted. Learn to live together. @0celo7

2

Koolman

Similarly for others

ACuriousMind

@skullpetrol What does it do?

0celo7

6:56 PM

@anonymous I was here first.

anonymous

@0celo7 So?

skullpetrol

Nothing very useful really @ACuriousMind :P

0celo7

@anonymous I shouldn't have to learn to live with invaders

skullpetrol

Build a wall :P

0celo7

@skullpetrol can't, on mobile

Mostafa

6:59 PM

@anonymous Don't you think it would be even better for you to have all your discussions on JEE in some dedicated room?

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