| Pages:
1
..
44
45
46
47
48
..
104 |
Oolong
Harmless
Posts: 2
Registered: 6-12-2015
Member Is Offline
Mood: No Mood
|
|
Are there any practical reasons for choosing a multi-neck flask with parallel side necks vs. angled side necks? I noticed from looking at a catalog
from a glassware manufacturer that they tend to come with different combinations of joint sizes, and wondered if they were both supposed to be used
for different purposes?
|
|
|
Sulaiman
International Hazard
Posts: 3721
Registered: 8-2-2015
Location: 3rd rock from the sun
Member Is Offline
|
|
I would have at least one of the outer necks at an angle because
I may want a thermometer or air leak or steam inlet in the liquid.
Things I can think of that may go into the necks;
Fractionating column, reflux condenser, thermometer, stirrer, addition funnel, air or steam inlet and probably others.
So only you can answer your question properly.
|
|
|
j_sum1
Administrator
Posts: 6333
Registered: 4-10-2014
Location: At home
Member Is Offline
Mood: Most of the ducks are in a row
|
|
I was converting some battery gunk -- MnO2 + impurities --> MnSO4 using nurdrage's method.
https://youtu.be/2gXByJkg0iY?t=203
I passed the exhaust gas through a NaOH scrubber to mop up any remaining SO2. My setup, (see below) seemed pretty effective. No sulfurous smell at
all (which is what I like in the absence of a fume hood.)
Once the intended reaction was complete, A white crystalline substance began to build up in the scrubber. I wasn't really even thinking about
byproducts, but since I have made it I thought I would collect and label. The liquid is still highly alkaline. What I would like to know is whether I
have made sodium sufite or sodium bisulfite. I am pretty certain it is sulfite but thought it worthwhile to check.
|
|
|
DraconicAcid
International Hazard
Posts: 4355
Registered: 1-2-2013
Location: The tiniest college campus ever....
Member Is Offline
Mood: Semi-victorious.
|
|
If it's highly alkaline, then it would be sodium sulphite. Sodium hydrogen sulphite would be only mildly basic.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
|
|
|
j_sum1
Administrator
Posts: 6333
Registered: 4-10-2014
Location: At home
Member Is Offline
Mood: Most of the ducks are in a row
|
|
Thanks for that DA. Crystals happily drying. 
|
|
|
j_sum1
Administrator
Posts: 6333
Registered: 4-10-2014
Location: At home
Member Is Offline
Mood: Most of the ducks are in a row
|
|
Phenol Red
I recently received an unlabelled vial of a reddish powder. A bit of experimentation and I discovered that it was an acid-base indicator. A bit
more careful measurement and I was able to identify it as phenol red. But it doesn't seem like a particularly useful indicator for the things I might
use it for. I understand that it has a few applications in biology and is also the indicator often used for swimming pool test kits. I don't have
any real use in those two areas. It changes colour over quite a wide range and without a colour matching card seems pretty useless.
So, is there anything interesting that could be done with it? I have a couple of grams.
|
|
|
diddi
National Hazard
Posts: 723
Registered: 23-9-2014
Location: Victoria, Australia
Member Is Offline
Mood: Fluorescent
|
|
you could prolly buy a replacement colour card from a pool store for a couple of bucks. the advantage is that it is able differentiate over a large
range of pH's with high accuracy rather than just turn at a particular acidity.
Beginning construction of periodic table display
|
|
|
j_sum1
Administrator
Posts: 6333
Registered: 4-10-2014
Location: At home
Member Is Offline
Mood: Most of the ducks are in a row
|
|
Yeah, but if I wanted that, I have some full range universal indicator. And some indicator strips. And a pH meter.
It was the multiplicity of phenol rings that caused me to wonder if something might be made from it.
|
|
|
The Volatile Chemist
International Hazard
Posts: 1981
Registered: 22-3-2014
Location: 'Stil' in the lab...
Member Is Offline
Mood: Copious
|
|
Clorinate it? I have no clue how chlorinated you could get it, but if you took a sample and passed chlorine through it, I'd assume you could at least
get that central carbon to a tertiary chloride, and turn the non-phenyl ring into a phenyl ring. Is this just spitballing? I have no clue if it'd
work. Versuchschemie.de had a bit of dye chem on it.
Two quick questions:
1. If you add boric acid to 'bicarb, do you get sodium borate or tetraborate? Is the resulting compound capable of precipitating Copper(II) borate
from a soluble Copper(II) salt?
2. What's the best way to purify HCl with lots of Iron(III) Chloride in it? I've seen the procedure which involves placing a container with the HCl
and a container with water in it in a larger container and letting it sit there. I have no suitable large container.
Thanks for any answers,
[Edited on 12-12-2015 by The Volatile Chemist]
|
|
|
gdflp
Super Moderator
Posts: 1320
Registered: 14-2-2014
Location: NY, USA
Member Is Offline
Mood: Staring at code
|
|
The central carbon on that class of dyes will not halogenate. Instead, you will get either di- or tetra- halo aromatic substitution, depending on
whether or not an excess of halogen is used. In the case of phenol red, bromination with bromine in acetic acid will yield bromophenol blue.(See
Vogel 3rd, pg. 990)
|
|
|
hyfalcon
International Hazard
Posts: 1003
Registered: 29-3-2012
Member Is Offline
Mood: No Mood
|
|
Bert, I have a question for you. How do you negate all the static build up in the air this time of year? You don't just avoid fireworking I'm sure.
When I run my hand down my dogs back and it crackles all the way down, I know not to touch anything that might not like static discharge.
|
|
|
The Volatile Chemist
International Hazard
Posts: 1981
Registered: 22-3-2014
Location: 'Stil' in the lab...
Member Is Offline
Mood: Copious
|
|
Quote: Originally posted by gdflp  | | The central carbon on that class of dyes will not halogenate. Instead, you will get either di- or tetra- halo aromatic substitution, depending on
whether or not an excess of halogen is used. In the case of phenol red, bromination with bromine in acetic acid will yield bromophenol blue.(See
Vogel 3rd, pg. 990) |
Makes sense. Interesting. If I ever get any bromine and phenol red, I'll have to give it a try. Perhaps halogenation with chlorine and bromine would
be good projects.
|
|
|
CuReUS
National Hazard
Posts: 928
Registered: 9-9-2014
Member Is Offline
Mood: No Mood
|
|
Is it possible to make a grignard reagent from a halo nitroarene,say 3-bromonitrobenzene ?
|
|
|
Crowfjord
Hazard to Others
Posts: 390
Registered: 20-1-2013
Location: Pacific Northwest
Member Is Offline
Mood: Ever so slowly crystallizing...
|
|
Grignards react with aromatic and aliphatic nitro compounds to give the disubstituted hydroxylamines. See for example J. Chem. Soc. Perkin Trans.
(1990) 2133-2138. 3-bromonitrobenzene would probably polymerize with the addition of magnesium.
|
|
|
CitricAcid
Harmless
Posts: 28
Registered: 13-12-2015
Member Is Offline
Mood: No Mood
|
|
Nitric Acid Safety,Quick Question.
I have a quick question about safety regarding nitric acid:Why is it classed as a level 4 health hazard on the MSDS and the NFPA 704? As far as I
know,getting it on the skin won't kill you unless you spill a whole beaker and all of it lands on your skin.
|
|
|
Agari
Banned
Posts: 160
Registered: 8-10-2015
Location: The Amine Group
Member Is Offline
Mood: Lowest Oxidation State
|
|
Skin contact isn't what will kill you,but rather inhalation. Inhaling nitric acid vapor will not only release toxic nitrogen dioxide gas directly into
your lungs,but will also paralyze the diaphragm and make it impossible to breathe. In fact, it is produced by the burning of nitromethane,which is
used as a booster in racing cars,drivers often have to wear face masks to avoid inhalation of the toxic vapors.
Element Collection Status:
Elements Acquired: 21/91
Latest: Lead (Pb)
Quantity: 12g
-----------------------------------------------------
|
|
|
Texium
|
Threads Merged
17-12-2015 at 17:05 |
The Garbage Guardian
Harmless
Posts: 2
Registered: 13-12-2015
Member Is Offline
Mood: No Mood
|
|
Hello, I'm new here, and am trying to build the sodium cell that len made. Does anyone know where to get the thick steel tube needed? All pipe from
hardware store is painted, galvanized, too small.
"Jerma and I relentlessly defend the garbage from all foreign invaders, utilizing techniques such as the people's elbow." -STAR_
|
|
|
arkoma
Redneck Overlord
Posts: 1763
Registered: 3-2-2014
Location: On a Big Blue Marble hurtling through space
Member Is Offline
Mood: украї́нська
|
|
I have 80ml piranha (60ml H2SO4, 20ml 12%h2o2) that I've used to remove red wine stubborns out of my 1l RBF. I've been doing crude KOH extractions
from oak ashes in my backyard. Surely some of my leachate from the ashes would neutralize it safely? No heavy metals or other nasties in it.
Arkansas is too pretty to pollute..........
"We believe the knowledge and cultural heritage of mankind should be accessible to all people around the world, regardless of their wealth, social
status, nationality, citizenship, etc" z-lib
|
|
|
JJay
International Hazard
Posts: 3440
Registered: 15-10-2015
Member Is Offline
|
|
It should be safe to pour out if you dilute it heavily.
|
|
|
CuReUS
National Hazard
Posts: 928
Registered: 9-9-2014
Member Is Offline
Mood: No Mood
|
|
| Quote: Originally posted by Crowfjord | | Grignards react with aromatic and aliphatic nitro compounds to give the disubstituted hydroxylamines. 3-bromonitrobenzene would probably polymerize
with the addition of magnesium. |
what if you reacted 3-nitrobenzaldehyde with R-MgX ? would the grignard attack the carbonyl group to give the alcohol.?
In morrison and boyd,it is written that grignard reactions cannot be done on nitro compounds as the nitro group will oxidise the grignard reagent .
|
|
|
elementcollector1
International Hazard
Posts: 2684
Registered: 28-12-2011
Location: The Known Universe
Member Is Offline
Mood: Molten
|
|
| Quote: Originally posted by The Garbage Guardian | | Hello, I'm new here, and am trying to build the sodium cell that len made. Does anyone know where to get the thick steel tube needed? All pipe from
hardware store is painted, galvanized, too small. |
A different hardware store.
Amazon.
EBay?
Elements Collected:52/87
Latest Acquired: Cl
Next in Line: Nd
|
|
|
The_Davster
A pnictogen
Posts: 2861
Registered: 18-11-2003
Member Is Offline
Mood: .
|
|
| Quote: Originally posted by The Garbage Guardian | | Hello, I'm new here, and am trying to build the sodium cell that len made. Does anyone know where to get the thick steel tube needed? All pipe from
hardware store is painted, galvanized, too small. |
http://www.mcmaster.com/#standard-steel-tubing/=10bn3ld
|
|
|
arkoma
Redneck Overlord
Posts: 1763
Registered: 3-2-2014
Location: On a Big Blue Marble hurtling through space
Member Is Offline
Mood: украї́нська
|
|
this would be a SECONDARY alcohol? it's honokiol, from magnolia tree bark.
"We believe the knowledge and cultural heritage of mankind should be accessible to all people around the world, regardless of their wealth, social
status, nationality, citizenship, etc" z-lib
|
|
|
gdflp
Super Moderator
Posts: 1320
Registered: 14-2-2014
Location: NY, USA
Member Is Offline
Mood: Staring at code
|
|
No, since the hydroxyl groups are connected to the aromatic rings, they behave very differently than they would if they were connected to a straight
sp3 carbon chain. Short explanation : this is due to the free circulation of electrons in the conjugated pi system greatly changing the reactivity.
They have their own nomenclature and are called <b>aryl</b> alcohols.
|
|
|
Crowfjord
Hazard to Others
Posts: 390
Registered: 20-1-2013
Location: Pacific Northwest
Member Is Offline
Mood: Ever so slowly crystallizing...
|
|
| Quote: Originally posted by CuReUS |
what if you reacted 3-nitrobenzaldehyde with R-MgX ? would the grignard attack the carbonyl group to give the alcohol.?
In morrison and boyd,it is written that grignard reactions cannot be done on nitro compounds as the nitro group will oxidise the grignard reagent .
|
Are benzaldehydes more easily reduced than aromatic nitro groups? If so, that might work to give the alcohol, as long as the nitrobenzaldehyde is kept
in excess. I imagine that in some cases the nitro would oxidize the grignard reagent rather than form a C-N bond. In that case, wouldn't the nitro
be reduced to a hydroxyl amine?
|
|
|
| Pages:
1
..
44
45
46
47
48
..
104 |
![[*]](images/xpblue/default_icon.gif){kind=icon}
