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#13886 From: "galopus" <galopus@...>
Date: Tue Sep 8, 2009 9:48 am
Subject: acetylene´s heat of formation
galopus
Offline Offline
Send Email Send Email
 
the acetylene can explode without the presence of oxygen (why).  is that related
to its hihg posisitve heat od formation??? please expplain and wy does that
happen.   thansk

#13887 From: "steve_geo1" <steve_geo1@...>
Date: Tue Sep 8, 2009 10:45 am
Subject: Re: acetylene´s heat of formation
steve_geo1
Offline Offline
Send Email Send Email
 
Acetylene undergoers explosive autopolymerization.

--- In thechemistrycluster@yahoogroups.com, "galopus" <galopus@...> wrote:
>
> the acetylene can explode without the presence of oxygen (why).  is that
related to its hihg posisitve heat od formation??? please expplain and wy does
that happen.   thansk
>

#13888 From: Sonali K <sonalikgt@...>
Date: Tue Sep 8, 2009 4:55 pm
Subject: ethanolamine
sonalikgt
Offline Offline
Send Email Send Email
 
Hi
I wanted to remove impurties from ethanolamine specially water. My ethanolamine
is liquid, is it because of water?
 
Thanks
 
Sona




[Non-text portions of this message have been removed]

#13889 From: "Stanley Latesky" <slatesk@...>
Date: Tue Sep 8, 2009 5:08 pm
Subject: RE: [The Chemistry Cluster] ethanolamine
sllatesky
Offline Offline
Send Email Send Email
 
ethanolamine is a liquid in most storage situations  since the melting
point is about 50 F (if you store it outside it will solidify  if it
gets cold enough)

you should be able to purify it by distillation and then store the
distillate over activated 4A molecular sieves.



From: thechemistrycluster@yahoogroups.com
[mailto:thechemistrycluster@yahoogroups.com] On Behalf Of Sonali K
Sent: Tuesday, September 08, 2009 12:55 PM
To: thechemistrycluster@yahoogroups.com
Subject: [The Chemistry Cluster] ethanolamine





Hi
I wanted to remove impurties from ethanolamine specially water. My
ethanolamine is liquid, is it because of water?

Thanks

Sona

[Non-text portions of this message have been removed]





[Non-text portions of this message have been removed]

#13890 From: galopus galopus <galopus@...>
Date: Tue Sep 8, 2009 9:08 pm
Subject: Re: [The Chemistry Cluster] Re: acetylene´s heat of formation
galopus
Offline Offline
Send Email Send Email
 
WHY??  EXPLAIN PLEASE,  POLYMERIZE INTO WHAT SUBSTANCE    THE PRODUCT OF
POLUMERIZATION




________________________________
From: steve_geo1 <steve_geo1@...>
To: thechemistrycluster@yahoogroups.com
Sent: Tuesday, September 8, 2009 5:45:21 AM
Subject: [The Chemistry Cluster] Re: acetylene´s heat of formation

 
Acetylene undergoers explosive autopolymerization.

--- In thechemistrycluster @yahoogroups. com, "galopus" <galopus@... > wrote:
>
> the acetylene can explode without the presence of oxygen (why). is that
related to its hihg posisitve heat od formation??? please expplain and wy does
that happen. thansk
>







[Non-text portions of this message have been removed]

#13891 From: John W <JohnWW@...>
Date: Wed Sep 9, 2009 3:44 am
Subject: Re: [The Chemistry Cluster] Re: acetylene´s heat of formation
johnwwxtraconz
Offline Offline
Send Email Send Email
 
See, for example:
http://en.wikipedia.org/wiki/Polyacetylene
http://www.answers.com/topic/acetylene
http://www.newworldencyclopedia.org/entry/Acetylene

Polyacetylene, as a linear polymer, is a conjugated polyene, with the formula
(CH)n:
-CH=CH-CH=CH-CH=CH-CH=CH- etc. Due to the interchangeability of the single and
double bonds, it is a good conductor of electricity, and absorbs all wavelengths
of light, like graphite.

From the Wikipedia article (BTW MacDiarmid originally came from my part of New
Zealand):
Discovery of the conductive properties of polyacetylene occurred in the early
1970s when a graduate student of Professor Hideki Shirakawa
accidentally polymerized acetylene with 1000 times the required amount
of catalyst. This revealed the polyacetylene to be a silver,
non-conductive film. Shirakawa later collaborated with physicist Alan J. Heeger
and chemist Alan G MacDiarmid, and discovered in 1976 that oxidation of this
material with iodine results in a 108-fold
increase in conductivity. The conductivity of this doped material
approaches the conductivity of the best available conductor, silver. This was
one of the first known examples of a conductive organic polymer. The three were
awarded the Nobel Prize in Chemistry in 2000 for their discoveries.[

John W.

--- On Wed, 9/9/09, galopus galopus <galopus@...> wrote:
From: galopus galopus <galopus@...>
Subject: Re: [The Chemistry Cluster] Re: acetylene´s heat of formation
To: thechemistrycluster@yahoogroups.com
Received: Wednesday, 9 September, 2009, 9:08 AM






 





                   WHY??  EXPLAIN PLEASE,  POLYMERIZE INTO WHAT SUBSTANCE    THE
PRODUCT OF POLUMERIZATION



____________ _________ _________ __

From: steve_geo1 <steve_geo1@yahoo. com>

To: thechemistrycluster @yahoogroups. com

Sent: Tuesday, September 8, 2009 5:45:21 AM

Subject: [The Chemistry Cluster] Re: acetylene´s heat of formation



Acetylene undergoers explosive autopolymerization.



--- In thechemistrycluster @yahoogroups. com, "galopus" <galopus@... > wrote:

>

> the acetylene can explode without the presence of oxygen (why). is that
related to its hihg posisitve heat od formation??? please expplain and wy does
that happen. thansk




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[Non-text portions of this message have been removed]

#13892 From: galopus galopus <galopus@...>
Date: Wed Sep 9, 2009 10:16 am
Subject: Re: [The Chemistry Cluster] Re: acetylene´s heat of formation
galopus
Offline Offline
Send Email Send Email
 
THANKS




________________________________
From: John W <JohnWW@...>
To: thechemistrycluster@yahoogroups.com
Sent: Tuesday, September 8, 2009 10:44:08 PM
Subject: Re: [The Chemistry Cluster] Re: acetylene´s heat of formation

 
See, for example:
http://en.wikipedia.org/wiki/Polyacetylene
http://www.answers. com/topic/ acetylene
http://www.newworld encyclopedia. org/entry/ Acetylene

Polyacetylene, as a linear polymer, is a conjugated polyene, with the formula
(CH)n:
-CH=CH-CH=CH- CH=CH-CH= CH- etc. Due to the interchangeability of the single and
double bonds, it is a good conductor of electricity, and absorbs all wavelengths
of light, like graphite.

From the Wikipedia article (BTW MacDiarmid originally came from my part of New
Zealand):
Discovery of the conductive properties of polyacetylene occurred in the early
1970s when a graduate student of Professor Hideki Shirakawa
accidentally polymerized acetylene with 1000 times the required amount
of catalyst. This revealed the polyacetylene to be a silver,
non-conductive film. Shirakawa later collaborated with physicist Alan J. Heeger
and chemist Alan G MacDiarmid, and discovered in 1976 that oxidation of this
material with iodine results in a 108-fold
increase in conductivity. The conductivity of this doped material
approaches the conductivity of the best available conductor, silver. This was
one of the first known examples of a conductive organic polymer. The three were
awarded the Nobel Prize in Chemistry in 2000 for their discoveries. [

John W.

--- On Wed, 9/9/09, galopus galopus <galopus@yahoo. com> wrote:
From: galopus galopus <galopus@yahoo. com>
Subject: Re: [The Chemistry Cluster] Re: acetylene´s heat of formation
To: thechemistrycluster @yahoogroups. com
Received: Wednesday, 9 September, 2009, 9:08 AM

 

WHY??  EXPLAIN PLEASE,  POLYMERIZE INTO WHAT SUBSTANCE    THE PRODUCT OF
POLUMERIZATION

____________ _________ _________ __

From: steve_geo1 <steve_geo1@ yahoo. com>

To: thechemistrycluster @yahoogroups. com

Sent: Tuesday, September 8, 2009 5:45:21 AM

Subject: [The Chemistry Cluster] Re: acetylene´s heat of formation

Acetylene undergoers explosive autopolymerization.

--- In thechemistrycluster @yahoogroups. com, "galopus" <galopus@... > wrote:

>

> the acetylene can explode without the presence of oxygen (why). is that
related to its hihg posisitve heat od formation??? please expplain and wy does
that happen. thansk




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#13893 From: "A Nagarajan" <nagarajan@...>
Date: Wed Sep 9, 2009 10:37 am
Subject: removal of water
chemnagarajan04
Offline Offline
Send Email Send Email
 
I want to remove water from keroscene, what chemicals or process i can use?
Thanks,
ANR


[Non-text portions of this message have been removed]

#13894 From: John W <JohnWW@...>
Date: Wed Sep 9, 2009 2:13 pm
Subject: Re: [The Chemistry Cluster] removal of water
johnwwxtraconz
Offline Offline
Send Email Send Email
 
In the first instance, if so much water is present that it separates out on the
bottom, the water can be removed simply by means of putting it (or the residue
left after decantation of most of the kerosene from an open vessel) through a
transparent separating funnel with a tap in its outlet, thereby enabling the
water to be poured away.

This would still leave the kerosene with a very small amount of water in it, the
two being miscible to the extent of only a small fraction of a percent at
saturation. Except if a very large amount of kerosene needs to be further
treated, and high purity and total absence of water were necessary, it would be
too costly to purify by redistilling the kerosene. This last trace of water
could, instead, be removed by salting it out - adding a hygroscopic ionic salt
soluble in water but insoluble in kerosene. Ordinary sodium chloride would do;
otherwise calcium chloride, although use of such chloride salts would be
unsuitable in unlined mild steel containers because they promote corrosion.

John W.

--- On Wed, 9/9/09, A Nagarajan <nagarajan@...> wrote:
From: A Nagarajan <nagarajan@...>
Subject: [The Chemistry Cluster] removal of water
To: thechemistrycluster@yahoogroups.com
Received: Wednesday, 9 September, 2009, 10:37 PM






 





                   I want to remove water from keroscene, what chemicals or
process i can use?

Thanks, 
ANR







[Non-text portions of this message have been removed]

#13895 From: galopus galopus <galopus@...>
Date: Wed Sep 9, 2009 3:55 pm
Subject: Re: [The Chemistry Cluster] removal of water
galopus
Offline Offline
Send Email Send Email
 
CaO  also can be used.........Remember that the humidity of thae air let water
appears also in the kerosene....




________________________________
From: John W <JohnWW@...>
To: thechemistrycluster@yahoogroups.com
Sent: Wednesday, September 9, 2009 9:13:18 AM
Subject: Re: [The Chemistry Cluster] removal of water

 
In the first instance, if so much water is present that it separates out on the
bottom, the water can be removed simply by means of putting it (or the residue
left after decantation of most of the kerosene from an open vessel) through a
transparent separating funnel with a tap in its outlet, thereby enabling the
water to be poured away.

This would still leave the kerosene with a very small amount of water in it, the
two being miscible to the extent of only a small fraction of a percent at
saturation. Except if a very large amount of kerosene needs to be further
treated, and high purity and total absence of water were necessary, it would be
too costly to purify by redistilling the kerosene. This last trace of water
could, instead, be removed by salting it out - adding a hygroscopic ionic salt
soluble in water but insoluble in kerosene. Ordinary sodium chloride would do;
otherwise calcium chloride, although use of such chloride salts would be
unsuitable in unlined mild steel containers because they promote corrosion.

John W.

--- On Wed, 9/9/09, A Nagarajan <nagarajan@godrejsar alee.com> wrote:
From: A Nagarajan <nagarajan@godrejsar alee.com>
Subject: [The Chemistry Cluster] removal of water
To: thechemistrycluster @yahoogroups. com
Received: Wednesday, 9 September, 2009, 10:37 PM

 

I want to remove water from keroscene, what chemicals or process i can use?

Thanks, 
ANR




[Non-text portions of this message have been removed]







[Non-text portions of this message have been removed]

#13896 From: galopus galopus <galopus@...>
Date: Wed Sep 9, 2009 3:57 pm
Subject: Re: [The Chemistry Cluster] removal of water
galopus
Offline Offline
Send Email Send Email
 
the also hahave nhibitors. if  the jet fuel has water in it it will solidifies
when traveling at high altite that is why they ad to it speciall inhiobitors to
do no let the formation of ice-  the jet will crahs if so...




________________________________
From: John W <JohnWW@...>
To: thechemistrycluster@yahoogroups.com
Sent: Wednesday, September 9, 2009 9:13:18 AM
Subject: Re: [The Chemistry Cluster] removal of water

 
In the first instance, if so much water is present that it separates out on the
bottom, the water can be removed simply by means of putting it (or the residue
left after decantation of most of the kerosene from an open vessel) through a
transparent separating funnel with a tap in its outlet, thereby enabling the
water to be poured away.

This would still leave the kerosene with a very small amount of water in it, the
two being miscible to the extent of only a small fraction of a percent at
saturation. Except if a very large amount of kerosene needs to be further
treated, and high purity and total absence of water were necessary, it would be
too costly to purify by redistilling the kerosene. This last trace of water
could, instead, be removed by salting it out - adding a hygroscopic ionic salt
soluble in water but insoluble in kerosene. Ordinary sodium chloride would do;
otherwise calcium chloride, although use of such chloride salts would be
unsuitable in unlined mild steel containers because they promote corrosion.

John W.

--- On Wed, 9/9/09, A Nagarajan <nagarajan@godrejsar alee.com> wrote:
From: A Nagarajan <nagarajan@godrejsar alee.com>
Subject: [The Chemistry Cluster] removal of water
To: thechemistrycluster @yahoogroups. com
Received: Wednesday, 9 September, 2009, 10:37 PM

 

I want to remove water from keroscene, what chemicals or process i can use?

Thanks, 
ANR




[Non-text portions of this message have been removed]







[Non-text portions of this message have been removed]

#13897 From: Edilson Ferreira <edilsonsfx@...>
Date: Wed Sep 9, 2009 6:17 pm
Subject: Re: [The Chemistry Cluster] removal of water
edifet
Offline Offline
Send Email Send Email
 
Much water use separation funnil by density, less water use sodium metallic

2009/9/9 A Nagarajan <nagarajan@...>

>
>
> I want to remove water from keroscene, what chemicals or process i can use?
> Thanks,
> ANR
>
> [Non-text portions of this message have been removed]
>
>
>



--
Prof. Ms. Edilson Ferreira
"A teoria guia, o experimento decide"
"The theory guides, the experiment decides"
(I.M. Kolthoff)


[Non-text portions of this message have been removed]

#13900 From: "A Nagarajan" <nagarajan@...>
Date: Sat Sep 12, 2009 12:41 pm
Subject: Moisture in starch
chemnagarajan04
Offline Offline
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We are using starch in our product,But it is obsorbing moisture from air while
keeping final product for so many days. Any chemicals can help to avoid this ? i
can use Caco3 ?
Regards,
ANR
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[Non-text portions of this message have been removed]

#13902 From: "jigs_jbhatt" <jigs_jbhatt@...>
Date: Thu Sep 17, 2009 3:05 pm
Subject: by increse a temperature of any solution, what change we got in its ph?
jigs_jbhatt
Offline Offline
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as per IP volume -1,by increse temp of buffer sol there will decrese in ph but
ph=temp, so how can it posible theoritically? pls reaply me on my email
address...........

#13904 From: "sherli" <sherli_sh33@...>
Date: Sat Sep 19, 2009 8:39 pm
Subject: Boiling point
sherli_sh33
Offline Offline
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In specification of melting and boiling point, we use paraphine.
what are the other substances we can use instead of araphine?

#13905 From: Augustin Jayaprakasam <angelin_augustin@...>
Date: Mon Sep 21, 2009 11:03 am
Subject: Re: [The Chemistry Cluster] Boiling point
angelin_augu...
Offline Offline
Send Email Send Email
 
Sometimes Sulfuric acid (not advisable) is also used for low boilers.  But
safety measures has to be strictly followed.




________________________________
From: sherli <sherli_sh33@...>
To: thechemistrycluster@yahoogroups.com
Sent: Saturday, September 19, 2009 4:39:11 PM
Subject: [The Chemistry Cluster] Boiling point


In specification of melting and boiling point, we use paraphine.
what are the other substances we can use instead of araphine?







[Non-text portions of this message have been removed]

#13911 From: "Steve_geo1" <steve_geo1@...>
Date: Tue Sep 29, 2009 11:28 pm
Subject: Beware (no subject) Sent by hihi.007
steve_geo1
Offline Offline
Send Email Send Email
 
Dear Friends:

hihi.007 sent a message to this group at 10:25 am. This post contained no
message other than a url. This is a highly poisonous url that will infect your
computer if you click on it. You cannot get rid of it. And once you click on any
choice, your computer is infected.

#13918 From: ochoaluver09
Date: Fri Oct 16, 2009 1:52 pm
Subject: Confused as to where to begin
ochoaluver09
Offline Offline
 
Ba(OH)2 is a strong base and ionizes completely to barium and hydroxide ions.
Calculate the pH of a 0.2 M solution of Ba(OH)2.

#13919 From: "nathanhaese" <nathanhaese@...>
Date: Fri Oct 16, 2009 2:31 pm
Subject: Re: Confused as to where to begin
nathanhaese
Offline Offline
Send Email Send Email
 
Dear Ocho;

You will like this.  It is simple.

Step-1.  When Ba(OH)2 completely ionizes, two hydroxide ions, OH-, go into
solution for every Ba(OH)2. So, if the solution was prepared to be 0.2M in
Ba(OH)2, then it is twice that, or 0.4M in OH-, after the Ba(OH)2 is dissolved.

Step-2.  There is an equilibrium between H+ and OH- through the reaction H2O <=>
H+ + OH-, the dissociation of water, with a constant Kw = [H+]*[OH-] = 10^-14. 
Since we know the OH- concentration is 0.4M, then we can calculate [H+] =
Kw/[OH-] = 10^(-14)/0.4 = 2.5*10^(-14).

Step-3.  Compute the pH using pH = - log([H+]) = - log (2.5*10^(-14)), or pH =
13.6.

Nathan

****************************************************************

Questions you may agonize over.

1.  How can some one say a solution is 0.2M in Ba(OH)2 when it dissociates into
Ba+2 and OH- ions?  There is no Ba(OH)2 in the water!  Well, when the question
used the units M, or molarity, what more precisely should have been used is F,
the formal concentration.  F is the concentration of the recipe.  It is useful
in preparing solutions.

2.  How can we say that OH- is 0.4M when some of the OH- ions react with H+ to
form water?  Isn't the OH- concentration a little less?   The answer is Yes, it
is a little less, but not much.  Just before the Ba(OH)2 was dissolved in the
water, the [H+] was 10^(-7).  After addition, the [H+] dropped to 2.5*10^(-14)
and took with it the corresponding OH-.  But notice how small these numbers are
compared to 0.4.  So, yes OH- is a little smaller, but the difference is too
small to worry about.  (You can calculate it, but that adds a little pain.)




--- In thechemistrycluster@yahoogroups.com, ochoaluver09 <no_reply@...> wrote:
>
> Ba(OH)2 is a strong base and ionizes completely to barium and hydroxide ions.
Calculate the pH of a 0.2 M solution of Ba(OH)2.
>

#13921 From: ochoaluver09
Date: Wed Oct 28, 2009 4:05 am
Subject: Balancing equations. In desperate need of help
ochoaluver09
Offline Offline
 
How do you balance these equations?

I am confused. My professor taught us in away that I had no idea as to how he
did it! I swear it sounded like he was talking French the whole time? How do you
know what the charges are? Can anyone help me with these examples he gave in
class please?


1. Mn^2+ + H2O2 + OH^- --------> MnO2 + H2O


2. Bi(OH)3 + SnO2^2- -------> Bi + H2O + SnO3^2-


3. Cr2O7^2- + H^+ + C2O4^2- ------> Cr^3+ + CO2 +H2O

4. Cl^- + ClO3^- + H^+ ------> Cl2 + ClO2 +H2O

#13922 From: ludwig_julca_83
Date: Wed Oct 28, 2009 5:54 pm
Subject: Re: Balancing equations. In desperate need of help
ludwig_julca_83
Offline Offline
 
Mn(2+) + H2O2 + 2OH- ---> MnO2 + 2H2O
4Bi(OH)3 + 6SnO2(2-) ----> 4Bi(0) + 6SnO3(2-) + 6H2O
Cr2O7(2-) + 14H+ + 3C2O4(2-) ----> 6CO2 + 2Cr(3+) + 7H2O
2Cl- + 2ClO3- + 4H+ ----> Cl2 + 2ClO2 + 2H2O

For a detailed explanation, look to "ion electron method" on a web search, or
ask in Yahoo! Answers.

--- In thechemistrycluster@yahoogroups.com, ochoaluver09 <no_reply@...> wrote:
>
> How do you balance these equations?
>
> I am confused. My professor taught us in away that I had no idea as to how he
did it! I swear it sounded like he was talking French the whole time? How do you
know what the charges are? Can anyone help me with these examples he gave in
class please?
>
>
> 1. Mn^2+ + H2O2 + OH^- --------> MnO2 + H2O
>
>
> 2. Bi(OH)3 + SnO2^2- -------> Bi + H2O + SnO3^2-
>
>
> 3. Cr2O7^2- + H^+ + C2O4^2- ------> Cr^3+ + CO2 +H2O
>
> 4. Cl^- + ClO3^- + H^+ ------> Cl2 + ClO2 +H2O
>

#13923 From: "wood1j" <wood1j@...>
Date: Wed Oct 28, 2009 7:53 pm
Subject: synthesis of aluminum
wood1j
Offline Offline
Send Email Send Email
 
given the oxidation reduction equation
Al + KOH + H2O --> KAl(OH)4 + H2

and the acid base reaction
KAl(OH)4 + H2SO4 + H2O --> KAl(SO4)2-12H2O

what are the balanced chemical equations and the overall chemical equation?

#13924 From: galopus galopus <galopus@...>
Date: Wed Oct 28, 2009 11:06 pm
Subject: Re: [The Chemistry Cluster] synthesis of aluminum
galopus
Offline Offline
Send Email Send Email
 
2Al + 2KOH + 6H2O --> 2KAl(OH)4 + 3H2

KAl(OH)4 + 2H2SO4 + 8H2O --> KAl(SO4)2-12H2O



 



________________________________
From: wood1j <wood1j@...>
To: thechemistrycluster@yahoogroups.com
Sent: Wed, October 28, 2009 2:53:56 PM
Subject: [The Chemistry Cluster] synthesis of aluminum

 
given the oxidation reduction equation
Al + KOH + H2O --> KAl(OH)4 + H2

and the acid base reaction
KAl(OH)4 + H2SO4 + H2O --> KAl(SO4)2-12H2O

what are the balanced chemical equations and the overall chemical equation?







[Non-text portions of this message have been removed]

#13927 From: zahra_guitar
Date: Fri Nov 6, 2009 7:39 pm
Subject: Instrumental Analysis
zahra_guitar
Offline Offline
 
in the instrumental analysis , we have a section that relates to the "Sample
Containers" or "Sample Holders".
Now, I want to know the advantages and disadvatages of "Cylindrical Cell"??

#13928 From: John W <JohnWW@...>
Date: Sat Nov 7, 2009 5:00 am
Subject: Re: [The Chemistry Cluster] Instrumental Analysis
johnwwxtraconz
Offline Offline
Send Email Send Email
 
Cylindrical cells to hold samples can be made any desired length that can be
accommodated by the particular model of spectrophotometer, with light traveling
longitudinally through the cylinder (the ends of which would have to be
something like fused quartz which transmits light well into the ultraviolet and
near infrared) where certain wavelengths are absorbed by the sample. However,
most desktop spectrophotometers are made to take fused-quartz cells measuring on
the inside 1 cm x 1 cm x 2 to 4 cm high, i.e. with a 1 cm light path through the
sample; but for very sensitive measurements of trace amounts of colored
compounds, or low light absorption at the wavelengths of interest, this may well
be an insufficient light path.

John W.

--- On Sat, 7/11/09, zahra_guitar <no_reply@yahoogroups.com> wrote:
From: zahra_guitar <no_reply@yahoogroups.com>
Subject: [The Chemistry Cluster] Instrumental Analysis
To: thechemistrycluster@yahoogroups.com
Date: Saturday, 7 November, 2009, 8:39 AM







 









       in the instrumental analysis , we have a section that relates to the
"Sample Containers" or "Sample Holders".

Now, I want to know the advantages and disadvatages of "Cylindrical Cell"??









     __._,_.__

[Non-text portions of this message have been removed]

#13929 From: John Edward <jeedward@...>
Date: Sun Nov 8, 2009 11:50 pm
Subject: BCBGC-10 Call for papers
jeedward
Offline Offline
Send Email Send Email
 
BCBGC-10 Call for papers
 
The 2010 International Conference on Bioinformatics, Computational Biology,
Genomics and Chemoinformatics (BCBGC-10) (website:
http://www.PromoteResearch.org) will be held during 12-14 of July 2010 in
Orlando, FL, USA.  BCBGC is an important event in the areas of bioinformatics,
computational biology, genomics and chemoinformatics and focuses on all areas
related to the conference.
 
The conference will be held at the same time and location where several other
major international conferences will be taking place. The conference will be
held as part of 2010 multi-conference (MULTICONF-10). MULTICONF-10 will be held
during July 12-14, 2010 in Orlando, Florida, USA. The primary goal of MULTICONF
is to promote research and developmental activities in computer science,
information technology, control engineering, and related fields. Another goal is
to promote the dissemination of research to a multidisciplinary audience and to
facilitate communication among researchers, developers, practitioners in
different fields. The following conferences are planned to be organized as part
of MULTICONF-10.
 

International Conference on Artificial Intelligence and Pattern Recognition
(AIPR-10)
 International Conference on Automation, Robotics and Control Systems (ARCS-10)
International Conference on Bioinformatics, Computational Biology, Genomics and
Chemoinformatics (BCBGC-10)
International Conference on Computer Networks (CN-10)
International Conference on Enterprise Information Systems and Web Technologies
(EISWT-10)
International Conference on High Performance Computing Systems (HPCS-10)
International Conference on Information Security and Privacy (ISP-10)
International Conference on Image and Video Processing and Computer Vision
(IVPCV-10)
International Conference on Software Engineering Theory and Practice (SETP-10)
International Conference on Theoretical and Mathematical Foundations of Computer
Science (TMFCS-10)
 
We invite draft paper submissions. Please see the website
http://www.PromoteResearch.org for more details.
 
Sincerely
John Edward
Publicity committee




[Non-text portions of this message have been removed]

#13931 From: rajesh bhardwaj <rkb_1973@...>
Date: Wed Nov 11, 2009 5:53 am
Subject: Help
rkb_1973
Offline Offline
Send Email Send Email
 
 I wll be grateful if someone provides me the following paper:
 
Design, synthesis and antidepressant activity of some N2-substituted nalidixic
acid hydrazides and their cyclized analogs.
Youssef, Adel F.; Omar, Farghaly A.; Elsherief, Hosney A.; Abuo-Rahma, Gamal El
Din A. A. Department of Pharmaceutical Medicinal Chemistry, Faculty of Pharmacy,
Assiut University, Assiut, Egypt. Bulletin of Pharmaceutical Sciences, Assiut
University (1998), 21(1), 15-26.

with regards
rajesh



       The INTERNET now has a personality. YOURS! See your Yahoo! Homepage.
http://in.yahoo.com/

[Non-text portions of this message have been removed]

#13934 From: "MD under construction" <jgfuentes87@...>
Date: Thu Nov 12, 2009 9:47 pm
Subject: Chemistry practice question
jgfuentes87
Offline Offline
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The energy required to dislodge electrons from sodium metal via the
photoelectric effect is 275 kJ/mol. What wavelength in nm of light has
sufficient energy per photon to dislodge an electron from the surface of sodium?

#13935 From: BRIAN JENSEN <brianejensen@...>
Date: Fri Nov 13, 2009 7:50 am
Subject: Re: [The Chemistry Cluster] Chemistry practice question
brianedwardj...
Offline Offline
Send Email Send Email
 
 
 
http://www.astronomynotes.com/light/s3.htm
Energy of light = h Ă— f
where h is a universal constant of nature called ``Planck's constant'' = 6.63 Ă—
10-34 J·sec.
275 *10^3J/mol. / (6.023*10^23 electrons per mole)/(6.63x10-34J-sec)
=275/6.023/6.63*10^(3+23-34) sec-1
=6.887*10^-8 sec-1
This is obviously wrong because frequency should be a high power of 10, not a
negative poser of 10. I got an F in Quantum mechanics.
Regards,
Brian Jensen

--- On Thu, 11/12/09, MD under construction <jgfuentes87@...> wrote:


From: MD under construction <jgfuentes87@...>
Subject: [The Chemistry Cluster] Chemistry practice question
To: thechemistrycluster@yahoogroups.com
Date: Thursday, November 12, 2009, 3:47 PM


 



The energy required to dislodge electrons from sodium metal via the
photoelectric effect is 275 kJ/mol. What wavelength in nm of light has
sufficient energy per photon to dislodge an electron from the surface of sodium?








[Non-text portions of this message have been removed]

#13937 From: "Lance C" <ld_corey@...>
Date: Sun Nov 15, 2009 6:17 pm
Subject: Re: [The Chemistry Cluster] Chemistry practice question
ld_corey
Offline Offline
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Hi,

The answer I got is 435.3 nm.

Brian, you forgot to multiply by the speed of light and I think your factor of
10 should be (3 - 23 - (-34) + power for speed of light + conversion of m to
nm).

Lance


--- In thechemistrycluster@yahoogroups.com, BRIAN JENSEN <brianejensen@...>
wrote:
>
>
>  
>  
> http://www.astronomynotes.com/light/s3.htm
> Energy of light = h Ă— f
> where h is a universal constant of nature called ``Planck's constant'' = 6.63
× 10-34 J·sec.
> 275 *10^3J/mol. / (6.023*10^23 electrons per mole)/(6.63x10-34J-sec)
> =275/6.023/6.63*10^(3+23-34) sec-1
> =6.887*10^-8 sec-1
> This is obviously wrong because frequency should be a high power of 10, not a
negative poser of 10. I got an F in Quantum mechanics.
> Regards,
> Brian Jensen
>
> --- On Thu, 11/12/09, MD under construction <jgfuentes87@...> wrote:
>
>
> From: MD under construction <jgfuentes87@...>
> Subject: [The Chemistry Cluster] Chemistry practice question
> To: thechemistrycluster@yahoogroups.com
> Date: Thursday, November 12, 2009, 3:47 PM
>
>
>  
>
>
>
> The energy required to dislodge electrons from sodium metal via the
photoelectric effect is 275 kJ/mol. What wavelength in nm of light has
sufficient energy per photon to dislodge an electron from the surface of sodium?
>
>
>
>
>
>
>
>
> [Non-text portions of this message have been removed]
>

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