The Periodic Table

DHMO

12:37 AM

Who uses v for frequency?

Bernard Meurer

1:03 AM

@DHMO That's a $\nu$

DHMO

@BernardMeurer oh, a ν

lol, vee and nu look the same here

$\nu$ then

Bernard Meurer

Yeah, it's a pain in the ass :p

user228700

5:46 AM

Hello everyone :-) Riight...no one is here yet.

user228700

Well, I was wondering if anybody knows the formula for bond order, which does not involve MO theory.

M.A.R.

6:20 AM

@Kaumudi I don't.

user228700

OK...

user228700

Also, hi! :-P

M.A.R.

Hey. I'm just leaving to do some studying.

user228700

OK...

user228700

6:41 AM

I've a quick question about back bonding.

user228700

Is $\pi$ back bonding different from simply back bonding? Wikipedia (which contrasts with the definition given in my textbook) suggests this...

user228700

Wikipedia:

user228700

$\pi$ backbonding, also called $\pi$ backdonation, is a concept from Chemistry in which electrons move from an atomic orbital on one atom to a $\pi$* antibonding orbital on a $\pi$-acceptor ligand.

user228700

My textbook:

user228700

user228700

6:46 AM

So..?

DHMO

11:51 AM

@Kaumudi I thought I told you before

orthocresol

12:07 PM

@Kaumudi pi backbonding is simply backbonding that occurs in a pi-type fashion. Nearly all the time, this is true. So for the most part, they are synonymous.

The term backbonding is most commonly seen in the context of transition metal complexes, which is what Wikipedia is describing.

The term I learnt to describe BF3 with is pπ-pπ bonding, but you can just go with what your textbook says, it's nothing more than a choice of word.

Furthermore, the parallel between Wikipedia's description and the case of BF3 is quite strong: you have "backdonation" of fluorine pi-type lone pair into the empty pi-type 2p on boron.

user228700

12:28 PM

@DHMO Ah, yes, u did...

DHMO

@Kaumudi my formula is based on the octet rule though

(8 x number of atoms - total outermost shell electron of each atom) / 2

user228700

@orthocresol Huh. What threw me off was the phrase "move from an atomic orbital to a $\pi*$ antibonding orbital.

user228700

@DHMO Yes, I remember ^.^

DHMO

@Kaumudi nice

user228700

Hey, BTW, how do u manage to remember those many common names for organic compounds?

DHMO

12:35 PM

hint: I don't

user228700

:?

user228700

Explain?

DHMO

I mean

I don't remember many common names

user228700

OK...

user228700

Is anybody familiar with the concept of degree of unsaturation? (🙏)

DHMO

12:42 PM

@Kaumudi here it is called the double bond equivalent

chem.libretexts.org/Core/Organic_Chemistry/Hydrocarbons/Alkenes/…

This site contains a formula

@Kaumudi but usually you can just the number of double bonds and the number of rings

user228700

The Wikipedia article wasn't helpful but that ^ is, thanks.

user228700

@DHMO Right, but my textbook gives the same formula so.

DHMO

and a triple bond counts as 2 @Kaumudi

user228700

Yeah :/ Wtf is up with that? Also, the site says:

DHMO

because you can make a triple bond into two double bonds without changing the number of atoms and electrons

user228700

12:51 PM

"For a compound to be saturated, there is one more hydrogen in a molecule when nitrogen is present."

user228700

But this is true only if the N atom comes in the middle.

DHMO

e.g. $\ce{CH3-C#C-CH3}$ is $\ce{C4H6}$

and $\ce{CH2=CH-CH=CH2}$ is also $\ce{C4H6}$.

@Kaumudi no, the keyword is one more hydrogen

user228700

Actually, no, never mind about Nitrogen. It makes sense.

DHMO

!!img/carbon suboxide

Chemobot

user228700

12:57 PM

@DHMO: ?

DHMO

@Kaumudi ignore that

user228700

Ur equations didn't render...

DHMO

6

A: MathJax in chat (ChatJax offshoot)

Based on the same principle, this little bookmarklet loads cancel in addition to mhchem: javascript:(function(){if(window.MathJax===undefined){var%20script%20=%20document.createElement(%22script%22);script.type%20=%20%22text/javascript%22;script.src%20=%20%22http://cdn.mathjax.org/mathjax/latest...

user228700

Duuude.

DHMO

???

user228700

1:02 PM

user228700

These are ur equations^

DHMO

@Kaumudi did you use the right script?

just copy the one i sent you

the one in the answer section, not the question section

user228700

I use mobile. Doesn't \ce work while typing questions on SE?

DHMO

it works in the main site

just not in chatrooms

user228700

Not on mobile either, apparently...

DHMO

1:04 PM

apparently

@orthocresol may be able to help you with that

!!img/inorganic benzene

Chemobot

user228700

No problem. I was able to understand, for the most part...

DHMO

@Kaumudi guess the following compound (don't look it up on the internet!):

user228700

?

DHMO

!!img/Cc1c([N+](=O)[O-])cc([N+](=O)[O-])cc1[N+](=O)[O-]

Chemobot

1:06 PM

No result found.

DHMO

oops

user228700

Huh.

DHMO

wait a minute

!!img/Cc1c(N(=O)=O)cc(N(=O)=O)cc1N(=O)=O

Chemobot

DHMO

@Kaumudi here. don't look it up on the internet!

user228700

1:10 PM

U want me to guess the name if this compound?

DHMO

yes

systematic name is good

common name is better

user228700

Dunno the common name. Is the IUPAC name (been awhile since I did this) 1-methyl 2,4,6-nitro benzene?

DHMO

not commas or spaces

and trinitro

user228700

Oh sh!t, yeah, trinitro.

user228700

So what's the common name and why did u want me to guess?

DHMO

1:15 PM

@Kaumudi 1-methyl-2,4,6-trinitrobenzene

1-methylbenzene is also known as toluene

so this guy is 2,4,6-trinitrotoluene

2,4,6-trinitrotoluene -> tnt

user228700

Yeah, Idk how and where to put the commas and dashes. I'll be revising/learning anew (some parts) again in a bit.

user228700

@DHMO Ah, OK...

user228700

What was that little exercise for? To show me how u remember the common names?

DHMO

no

it was just for fun

user228700

:-P Alright.

user228700

1:20 PM

U're most passionate about Chemistry?

DHMO

mathematics

and physics

user228700

OK, cool.

orthocresol

1:40 PM

I don't know how to get MathJax on mobile chat.

M.A.R.

1:50 PM

I don't know how to get MathJax on mobile chat.

orthocresol

You don't MathJax how to chat get on know mobile.

M.A.R.

I chat how to mobile get MathJax on don't know.

orthocresol

2:25 PM

Seems like I have infinite power here.

DHMO

@orthocresol that means your time is zero

orthocresol

Loong is away, Martin is away, jonsca does a lot of stuff but isn't here super often, and Manish is busy.

DHMO

in other words, you have no time here

M.A.R.

@orthocresol And infinite responsibility?

Any time now your back bends

orthocresol

@M.A.R. Infinite responsibility to suspend users

M.A.R.

2:27 PM

That's not . . . THAT'S CHEATING

orthocresol

New feed items: "Multiple question about alkanes/alkenes" This doesn't look good...

DHMO

@orthocresol those are questions that I often have, as a very beginner

M.A.R.

@orthocresol It's so Schrodingery. One question but many questions.

orthocresol

@DHMO I don't mean to be rude, but beginner or not, there's no difference. Too broad is too broad.

On top of that, I'm fairly sure some have been answered here before.

DHMO

@orthocresol what is broad? maybe it would be alright if we split it into 4 separate questions?

M.A.R.

2:30 PM

You're a mod. Your rude button doesn't exist

DHMO

the 1st question is broad though

the other questions are fine

orthocresol

@M.A.R. **** you

*#$&@#$&@#^$&@^$

$(($*!(#*@&$#@^&*@#$^!@)$(#)$(

wait what

The first question isn't even a question. You don't produce alkanes by some magic chemical reaction. You dig them out of the ground and separate them.

DHMO

@orthocresol I actually don't know how to answer q3

could you answer it here?

orthocresol

15

Q: Are long Oxygen molecules possible?

Are large oxygen containing molecules possible? Either large rings, or chains with hydrogen atoms at the ends. Like this: $\ce{H-O-O-O-O-O-O-O-O-O-... -O-O-O-O-O-H}$

molecules

33

Q: Why does Sulphur, but not Oxygen, catenate?

Oxygen is a rather boring element. It has only two allotropes, Oxygen and Ozone. Oxygen has a double bond, and Ozone has a delocalised cloud, giving rise to two "1.5 bonds". On the other hand, Sulphur has many stable allotropes, and a bunch of unstable ones as well. The variety of allotropes,...

inorganic-chemistry bond allotropes

DHMO

thanks

orthocresol

2:39 PM

Ok, time to commence cleanup of mhchem in titles.

DHMO

@orthocresol Hey, what is wrong with sulphur?

orthocresol

IUPAC uses sulfur.

M.A.R.

@orthocresol Yawn

DHMO

@orthocresol what.... it's a language difference

M.A.R.

@orthocresol And neither S not O should be capitalized.

orthocresol

2:41 PM

@M.A.R. Yes, I fixed all of that.

M.A.R.

Damn. You're too good.

DHMO

CO2 is called dioxyde de carbone in French

M.A.R.

You would've been a seal god if you liked ice cream as much as ice cream deserves to be loved.

orthocresol

@DHMO Sulfur is not used widely in UK anymore.

M.A.R.

@DHMO Thank you for this information. Now I can conquer the world with it.

DHMO

2:43 PM

@M.A.R. I'm just saying you can't force every name to conform to the English IUPAC rules used in a specific region

@orthocresol alright

orthocresol

IUPAC rules don't apply only to America.

M.A.R.

@DHMO IUPAC is global.

DHMO

so French must use the name "carbon dioxide" instead of "dioxyde de carbone"?

orthocresol

What sort of argument is that, that's a different language altogether.

DHMO

so is American English and British English different

M.A.R.

2:45 PM

@DHMO No.

orthocresol

Last I checked, there's no language called American English. Only English.

I have no issue if anybody wants to use -ize or color.

DHMO

@orthocresol alright

orthocresol

But I will correct sulphur to sulfur and aluminum to aluminium.

M.A.R.

Aluminium

ALUMINIUM

ALLLLUUUUUUUMINNNUMMMM

orthocresol

Not recognised as a word.

M.A.R.

2:47 PM

I sincerely apologise for my transgressions.

Aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum aluminum alu…

If you trash the message, that's a cheap shot.

DHMO

@M.A.R. If I were him, I would edit the message

@orthocresol Canada uses both sulfur and sulphur

M.A.R.

@DHMO IUPAC only uses 'sulfur'.

DHMO

@M.A.R. source?

M.A.R.

@DHMO nature.com/nchem/journal/v1/n5/full/nchem.301.html

DHMO

@orthocresol source above claims that "aluminum" is accepted in IUPAC

orthocresol

2:58 PM

IUPAC notes "The alternative spelling ‘aluminum’ is commonly used."

DHMO

IUPAC forbids sulphur

but does not ban aluminum

M.A.R.

@DHMO Your point being? Why is it better not to use the alternative spelling?

orthocresol

Aluminium is correct-er.

DHMO

@M.A.R. my point being there is no point correcting posts containing "aluminum" to "aluminium" if IUPAC accepts it

orthocresol

Call it style if you prefer.

M.A.R.

3:01 PM

@DHMO There is some point.

DHMO

@M.A.R. such as?

M.A.R.

This isn't 'realize' vs. 'realise'. That would be pointless.

In this case, one spelling is superior.

'cause it's preferred.

DHMO

@M.A.R. do you go around correcting ethanoic acid to acetic acid, if that is preferred?

M.A.R.

See DHMO, I have better things to do than argue semantics that has no use. If you want, you can argue with chemobot.

DHMO

@orthocresol do you go around correcting ethanoic acid to acetic acid, if that is preferred?

M.A.R.

3:03 PM

I'm certain he's obedient and listens carefully to all your arguments.

user228700

4:02 PM

@orthocresol U think it'll ever be possible? Been struggling :'-(

Hippalectryon

4:26 PM

o/

9-BBN

5:11 PM

Hollo

Aaron Abraham

0

Q: Why would breathing pure oxygen be a bad idea?

My textbook mentions that SCUBA tanks often contain a mixture of oxygen and nitrogen along with some helium which serves as a diluent. Now as I remember it, divers take care not to surface too quickly because it results in 'the Bends', which involves the formation of nitrogen bubbles in the blo...

everyday-chemistry gas-laws

Any ideas people?

9-BBN

Oxygen toxicity

Oxygen toxicity is a condition resulting from the harmful effects of breathing molecular oxygen (O 2) at increased partial pressures. It is also known as oxygen toxicity syndrome, oxygen intoxication, and oxygen poisoning. Historically, the central nervous system condition was called the Paul Bert effect, and the pulmonary condition the Lorrain Smith effect, after the researchers who pioneered its discovery and description in the late 19th century. Severe cases can result in cell damage and death, with effects most often seen in the central nervous system, lungs and eyes. Oxygen toxicity is a concern...

This is a quality article

There is a "underwater" paragraph en.wikipedia.org/wiki/Oxygen_toxicity#Underwater :)

If you have troubles with to much information put the article into NVivo software ^^

Anonymous

Can someone help with a thermochemistry doubt here ?

Anonymous

1

Q: What is the correct definition of Hydration Enthalpy and why is it always negative?

The first definition of hydration enthalpy I found on the net is : The hydration enthalpy is the enthalpy change when $1$ mole of gaseous ions dissolve in sufficient water to give an infinitely dilute solution. Hydration enthalpies are always negative. Another definition I found in a b...

physical-chemistry thermodynamics

9-BBN

5:34 PM

Well that is a bit complicated

But the statement is true ^^

user116211

@ortho, The uncertainty principle post izz butiful; +1.

user116211

It's thrilling to dig your posts ;)

user116211

I also wrote a detailed post on Uncertainty Principle right from the scratch - from Lagrange Brackets and canonical transformations. but that's another point.

9-BBN

@S007 $$\Delta H_{hydr} = \Delta_G U + \Delta H_{hydr} (cation)+ \Delta H_{hydr} (anion)\$$

$\Delta H_{hydr} = \Delta_G U + \Delta H_{hydr} (cation)+ \Delta H_{hydr} (anion)$

I have not a really good proof but it could something like this

user116211

@9-BBN Horror

user116211

5:42 PM

use \textrm.

9-BBN

@MAFIA36790 why ?

@MAFIA36790 do it for me ;)

user116211

okay; wait...

user116211

$$\Delta H_\textrm{hydr} = \Delta_G U + \Delta H_\textrm{hydr}~{\rm (cation)}+ \Delta H_\textrm{hydr}~{\rm (anion)}$$

user116211

@M.A.R. o/

M.A.R.

\o

@AaronAbraham IIRC it's related to gas physics

Oh wait.

Yeah, that's your second paragraph.

Isn't pure oxygen too dense?

@AaronAbraham I found the answer. Posting.

user116211

5:54 PM

WoW! Long day frustrated with Physics reviews; here comes Chem's very own HW:

user116211

0

Q: limiting Reagent Summary sheett

silver (1) sulfide with hydroelectric acid to form silver (1) chloride and dihdrogen sulfide. In one reaction 30 of silver (1) sulfide reacts with 10 grams of hydrochloric acid write balanced equation 2) determine limiting reagent 2a) convert reactant silver (1) sulfide to moles and then to a...

homework

M.A.R.

@MAFIA36790 Limiting reagent summary shit

user116211

Don't insult this valid question.

user116211

I've upvoted; so should you.

orthocresol

6:15 PM

Can someone write the HW comment for me?

user116211

!!greet/@nworb99

Chemobot

Welcome to The Periodic Table @nworb99! Here are our chat guidelines and it's recommended that you read them. If you want to turn Mathjax on, follow the instructions in this answer. Happy chatting!

user116211

@orthocresol What comment?

orthocresol

Nvm, I've done it.

nworb99

@MAFIA36790 hey thanks for the community wiki thing instructions, and the greeting as well

didn't realize the question was already being discussed here, too, whoops

user116211

6:20 PM

sure; that's my job as a responsible user here.

Chemobot

Welcome to The Periodic Table @nworb99! Here are our chat guidelines and it's recommended that you read them. If you want to turn Mathjax on, follow the instructions in this answer. Happy chatting!

user116211

@chem you okay?

user116211

._.

user116211

@hippa Halp!!

Hippalectryon

@MAFIA36790 O_o

nworb99

6:25 PM

I suppose I should take that as flattering...?

!!test

edited !

!!greet/@nwor

Welcome to The Periodic Table @nwor! Here are our chat guidelines and it's recommended that you read them. If you want to turn Mathjax on, follow the instructions in this answer. Happy chatting!

M.A.R.

Oh, Maf did it already.

Welcome to chat anyway.

nworb99

6:26 PM

third time's the charm

thanks!

M.A.R.

The second time doesn't count though.

That was chemobot becoming sentient.

1

A: Why would breathing pure oxygen be a bad idea?

Our body is used to the environment around us. Once you change part of the environment, you have to be ready for the consequences. Inhaling pure oxygen is the cause for what is known as oxygen toxicity. Oxygen toxicity is a condition resulting from the harmful effects of breathing molecular...

nworb99

touche

user116211

Is @Chemobot Ultron?

M.A.R.

I wouldn't have posted an answer if I knew you already have.

But mine uses correct Wikipedia-style citation, so it's obvious SUPERIOR.

Bow down to my answer.

Like, right now.

nworb99

!!bow_down

user116211

6:28 PM

downvoting...

M.A.R.

@MAFIA36790 Don't be a devil's advocate

@MAFIA36790 Hey no fair

I used a pretty picture too

user116211

Oh @M.A.R.; last night the h bar got muted for 5 mins.

M.A.R.

@MAFIA36790 Why?

Ocleo rampaging again or something?

user116211

Some user was flagging things continuously.

M.A.R.

Or was Trump vs. Clinton getting too hot?

user116211

6:30 PM

@M.A.R. yes...

user116211

@M.A.R. yes, yes....

M.A.R.

@MAFIA36790 That's an unfortunately familiar scene.

user116211

Our mod talked with him; but I don't think he got affected at all ;)

M.A.R.

Of course he didn't

And of course it's always a he.

user116211

He is over-sensitive? Maybe ;)

user116211

6:33 PM

He jokes often about flagging; but sometimes it's bothering.

user116211

He doesn't take it seriously.

user116211

Anyways, I don't like politics talking in any room, especially the h bar.

user116211

ARTofCode mentioned that they inactivated another chatroom for too much political arguments.

M.A.R.

CardOfOat is one of the regular mods of chat.

user116211

in The h Bar, 22 hours ago, by MAFIA36790

@MetaEd He is the Grim Reaper here. We really fear him a lot.

M.A.R.

6:38 PM

Who?

user116211

@M.A.R. ARTofCode.

M.A.R.

And MetaEd in h bar?

@MAFIA36790 Well, he's as old as me, so there.

FEAR ME MERE OLDER AND YOUNGER MORTALS

user116211

@M.A.R. yeh; and now he comes there for routine check up.

M.A.R.

@MAFIA36790 It's just one day, get over it.

You're lucky Shog isn't watching you.

user116211

@M.A.R. flagging as against democracy.

user116211

6:41 PM

@M.A.R. I would love one day to talk with him.

M.A.R.

@MAFIA36790 Well, he sometimes chats in the Tavern.

He's just a really wise man.

user116211

okay.

M.A.R.

yako.

user116211

Anyways, I'm off from chat now; bye @M.A.R. and all.

M.A.R.

\o

nworb99

6:44 PM

bon voyage

orthocresol

Bye

M.A.R.

7:31 PM

@Vedant please pay attention when you're editing. If you leave important problems with the post, I will reject the edit.

Edits shouldn't be trivial.

Esp. edits from users with less than 2k rep.

M.A.R.

7:56 PM

Thought about this answer?

0

A: What is the chemical structure of ceramic nonstick coating on pans?

There are MANY different types of ceramics and thus many different chemical formulas and structures. However, most have an oxide, nitride, or carbide ina crystalline structure. Referring to chemical structure, however, would include combinations of both ionic and covalent bonds, which are deter...