| Topic: |
Science > Physics |
| User: |
"Maleki" |
| Date: |
10 Mar 2005 10:34:29 AM |
| Object: |
Chemists! |
I know next to nothing about chemistry. But each time I took
a glance into it I found it a high-school level discipline
diligently adhered to only because the bag of tools required
contain not too many ways of approach past measuring mass
and temperature of something :-(
Here I have an American chemistry book in front of me, its
NINTH edition, priced over $160 U.S. Dollars and being
taught right now in U.S. colleges, and it refers to the
earth's acceleration of gravity as "Gravitational
Constant"... . Explains, defines, and names it as that.
There are all sorts of mistakes. So many that I noticed
something at last. The magic number "3". In _any_ chapter I
read, so far, (I've read five now) as soon as the subject
begins to be a consistent interplay of three independent
concepts that have thier own rules, the four chemists who
wrote the book get confused and make mistakes expressing
themselves. That's the limit of what they could do, and here
they are writing text book for colleges, lasting nine
editions.
Say, in Ch. 5, they're trying to explain the trivial concept
of "enthalpy" (fucking mouthfilling word for an obvious
concept, no wonder those here are so prone to shoot names at
us). There's convention about it, and there's logic, and
there's of course English language. Three independent
constructions, yet all involved in explaining the subject to
others. They can't hack it! They can't put all three
together.
Somewhere else, they combine two solids that after reaction
yield some water in which the products proceed to dissolve,
then their treatment of the problem turnes out to be one
that considers water the solvent and not part of the
reaction. Who are these bozos? They've even included a
picture of themselves in the text, all four.
There are a zillion chemsitry books in the market. It's as
disgusting as Google. Try to find the most obvious type of
information, but one that resides adjacent to a
universe-full of crap for the laymen. See if Google gets you
there.
--
"harche bAshad bAz nAmash masnad ast
gar ziyAnash dah bovad sudash sad ast"
- Parvin E'tesami
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| User: "Morituri-|-Max" |
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| Title: Re: Chemists! |
10 Mar 2005 11:59:12 AM |
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"Maleki" <maleki_m_@hotmail.com> wrote in message
news:dmyywvmk5z67.1f8ffzatv9mbo.dlg@40tude.net...
I know next to nothing about chemistry.
Here I have an American chemistry book in front of me, its
NINTH edition, priced over $160 U.S. Dollars and being
taught right now in U.S. colleges
There are all sorts of mistakes.
Or so you think, since you just said you don't know hardly anything about
it.
Sad.
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| User: "Maleki" |
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| Title: Re: Chemists! |
11 Mar 2005 09:47:23 AM |
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On Thu, 10 Mar 2005 17:59:12 GMT, Morituri-|-Max wrote:
"Maleki" <maleki_m_@hotmail.com> wrote in message
news:dmyywvmk5z67.1f8ffzatv9mbo.dlg@40tude.net...
I know next to nothing about chemistry.
Here I have an American chemistry book in front of me, its
NINTH edition, priced over $160 U.S. Dollars and being
taught right now in U.S. colleges
There are all sorts of mistakes.
Or so you think, since you just said you don't know hardly anything about
it.
Sad.
You must be female.
--
"farizeye hajj dar majmu'eye khod yek vasileye
vAghe'an momtAz va mo'asser barAye ehyA' va
tezkAre sonnate hazrate ebrAhim dar jahate
khodAparasti va eslAhe gholub ast."
- Mehdi Bazargan
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| User: "g" |
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| Title: Re: Chemists! |
10 Mar 2005 04:25:22 PM |
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I am not a chemist, either. However, I get caught
sometimes reading chemistry books. I also read
about a few other things... including biology and,
my own personal (subjective) opinion is that it is
less ambiguous for me to learn a new term, with a
good ontology. (I mean "ontology" here not in the
conventional sense, but in the sense it is used by
computer programmers, where it consists in the
logic cues, some inclusive, some exclusive, to
remove any "machine logic ambiguity.")
My pet peeve about biology esoterica is that lots
of the words they use come off to NON-biologists
as meaning something totally absurd. They speak
of plants that want to be eaten, of genes (codes is
what they are) as being altruistic or selfish, and one
of the greatest contributors to biology, Francis Crick,
himself, used the word "dogma" in the phrase all
biologists salivate over when they say it, "the central
dogma of molecular biology." Don't get me wrong.
Dr. Crick (along with cohorts) gave genetics a giant
leap forward, and -- like an 8-hundred pound
gorilla, who can sleep anywhere he damned well
pleases -- a person who does that and gets a Nobel
Prize for it, cannot be criticized.
It's just the people outside the field who get confused
by such usages. Anybody who is even just barely
science literate knows that dogma and science are
totally incompatible things. Crick used the word in
a metaphorical way, for emphasis. But the problem
is that, if you don't know that, TOUGH !
Yet, when legislation is passed limiting what biologists
can do in their laboratories, toward developing new
pharmaceuticals, or coming up with information useful
in human organ transplants, or useful toward treating
cancer... due to voters writing in to raise hell about
some non-issue they think is an issue, because they
take something literally (and keep in mind that very
few legislators or executives are biologists) the
biologists gripe about how stupid everybody outside
the field is.
So, the bottom line for me is: If I want to learn about
something, thinking it makes sense as written, and end
up thinking the writer is a total nut case, it would be
better for that writer AND me, if I had a clue when he
uses "wants" instead of "has a propensity to," "dogma"
instead of a "general rule," and that sort of thing.
Maybe when the biologists talk among themselves, it
makes them feel brilliant to see people's faces as the
think, "***** !" But, whether the altruistic benefit
of that conceit is offset by the selfish amount of money
they lose in grants and stuff to those who sound as if
they made some sense.
g
"Maleki" <maleki_m_@hotmail.com> wrote in message
news:dmyywvmk5z67.1f8ffzatv9mbo.dlg@40tude.net...
I know next to nothing about chemistry. But each time I took
a glance into it I found it a high-school level discipline
diligently adhered to only because the bag of tools required
contain not too many ways of approach past measuring mass
and temperature of something :-(
Here I have an American chemistry book in front of me, its
NINTH edition, priced over $160 U.S. Dollars and being
taught right now in U.S. colleges, and it refers to the
earth's acceleration of gravity as "Gravitational
Constant"... . Explains, defines, and names it as that.
There are all sorts of mistakes. So many that I noticed
something at last. The magic number "3". In _any_ chapter I
read, so far, (I've read five now) as soon as the subject
begins to be a consistent interplay of three independent
concepts that have thier own rules, the four chemists who
wrote the book get confused and make mistakes expressing
themselves. That's the limit of what they could do, and here
they are writing text book for colleges, lasting nine
editions.
Say, in Ch. 5, they're trying to explain the trivial concept
of "enthalpy" (fucking mouthfilling word for an obvious
concept, no wonder those here are so prone to shoot names at
us). There's convention about it, and there's logic, and
there's of course English language. Three independent
constructions, yet all involved in explaining the subject to
others. They can't hack it! They can't put all three
together.
Somewhere else, they combine two solids that after reaction
yield some water in which the products proceed to dissolve,
then their treatment of the problem turnes out to be one
that considers water the solvent and not part of the
reaction. Who are these bozos? They've even included a
picture of themselves in the text, all four.
There are a zillion chemsitry books in the market. It's as
disgusting as Google. Try to find the most obvious type of
information, but one that resides adjacent to a
universe-full of crap for the laymen. See if Google gets you
there.
--
"harche bAshad bAz nAmash masnad ast
gar ziyAnash dah bovad sudash sad ast"
- Parvin E'tesami
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| User: "tadchem" |
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| Title: Re: Chemists! |
11 Mar 2005 08:19:54 AM |
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g wrote:
...it is
less ambiguous for me to learn a new term, with a
good ontology. (I mean "ontology" here not in the
conventional sense, but in the sense it is used by
computer programmers, where it consists in the
logic cues, some inclusive, some exclusive, to
remove any "machine logic ambiguity.")
Kudos for your recognisition of the disparate uses of the term
'ontology' on separate fields.
My pet peeve about biology esoterica is that lots
of the words they use come off to NON-biologists
as meaning something totally absurd. They speak
of plants that want to be eaten, of genes (codes is
what they are) as being altruistic or selfish, and one
of the greatest contributors to biology, Francis Crick,
himself, used the word "dogma" in the phrase all
biologists salivate over when they say it, "the central
dogma of molecular biology."
Imprecision in technical speech has several origins. In particular the
anthropomorphism which you refer to is the result of laziness and
carelessness.
The creation of totally novel words to represent totally novel concepts
is not unknown - "laser" is a prime example. But it is not frequent
either.
In the sciences we routinely deal with new concepts, and usually end up
adopting/adapting words from other contexts - preferably with explicit
new definitions. When the new definitions are insufficiently explicit
or totally omitted, the communications that use them become imprecise.
Don't get me wrong.
Dr. Crick (along with cohorts) gave genetics a giant
leap forward, and -- like an 8-hundred pound
gorilla, who can sleep anywhere he damned well
pleases -- a person who does that and gets a Nobel
Prize for it, cannot be criticized.
Anybody can be criticized. Especially on UseNet. You have only to
read a few posts - usually the lead post in most threads in these
physics NGs - to find vehement criticism of Dr. Einstein and his ideas.
I myself have had some less-than-flattering things to say about Dr.
Pauling, and I feel Dr. Hawking is somewhat overrated.
What counts is the extent to which empirical observations can validate
the ideas presented - or the criticisms thereof.
It's just the people outside the field who get confused
by such usages. Anybody who is even just barely
science literate knows that dogma and science are
totally incompatible things. Crick used the word in
a metaphorical way, for emphasis. But the problem
is that, if you don't know that, TOUGH !
This point brings us back to the fundamental purpose of communication -
to make one's ideas understood by another.
It is for this reason that words are defined and
grammatical/mathematical rules are employed in their use. Those who
cannot make themselves precisely understood by their audience may as
well be shouting/pissing into the wind.
Especially within the context of specialized fields of study, where
specialized words represent specialized meanings, it is essential to
adhere to the conventional/standardized definitions and rules is use
for words. [I repeatedly must make this point to some raving crank who
thinks he has overthrown all of physics with some flash of insight, but
is unable to communicate the alleged idea in a detailed and unambiguous
manner.]
Yet, when legislation is passed limiting what biologists
can do in their laboratories, toward developing new
pharmaceuticals, or coming up with information useful
in human organ transplants, or useful toward treating
cancer... due to voters writing in to raise hell about
some non-issue they think is an issue, because they
take something literally (and keep in mind that very
few legislators or executives are biologists) the
biologists gripe about how stupid everybody outside
the field is.
Physicists, chemists, and others are also forced to endure the tyrrany
of decisions made by people with no understanding of the situation and
no interest in the outcome, just political agendas.
So, the bottom line for me is: If I want to learn about
something, thinking it makes sense as written, and end
up thinking the writer is a total nut case, it would be
better for that writer AND me, if I had a clue when he
uses "wants" instead of "has a propensity to," "dogma"
instead of a "general rule," and that sort of thing.
Better still to totally ignore a writer who cannot communicate
precisely, as you can never be 100% sure that you are interpreting the
writer's remarks as intended. There are plenty of people out there who
both know what they are talking about *and* can make themselves clearly
understood.
Maybe when the biologists talk among themselves, it
makes them feel brilliant to see people's faces as the
think, "***** !" But, whether the altruistic benefit
of that conceit is offset by the selfish amount of money
they lose in grants and stuff to those who sound as if
they made some sense.
Which brings us to another, more disingenuous origin for imprecision in
technical communications. The deliberate use of 'lingo' or argot by
specific groups (to conceal trade secrets while allowing them to speak
to each other openly in front of outsiders) traces back at least to the
Middle Ages, and may even be involved in the legendary story of the
Tower of Babel.
Many groups such as trade guilds, thieves' groups, healers, and
alchemists used obscure words such as astrological terms as code words
or synonyms for other words to confound eavesdroppers.
Tom Davidson
Richmond, VA
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| User: "Uncle Al" |
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| Title: Re: Chemists! |
10 Mar 2005 01:03:01 PM |
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Maleki wrote:
I know next to nothing about chemistry.
One doubts that will shorten this post.
Here I have an American chemistry book in front of me, its
NINTH edition, priced over $160 U.S. Dollars and being
taught right now in U.S. colleges, and it refers to the
earth's acceleration of gravity as "Gravitational
Constant"... . Explains, defines, and names it as that.
Uncle Al finds it difficult to state which of the five major branches
of chemistry - inorganic, organic, analytical, physical, theoretical -
is concerned with gravitation. Feynman was eloquent about the
contents of Official textbooks.
Textbooks are expensive because they can be. Students must come out
of formal education so deeply in debt that their whole lives, given
compassionate income redistribution, will barely get them back to the
rim of the hole. The Red Queen gambit is extremely useful to the
ruling classes.
There are all sorts of mistakes. So many that I noticed
something at last. The magic number "3". In _any_ chapter I
read, so far, (I've read five now) as soon as the subject
begins to be a consistent interplay of three independent
concepts that have thier own rules, the four chemists who
wrote the book get confused and make mistakes expressing
themselves. That's the limit of what they could do, and here
they are writing text book for colleges, lasting nine
editions.
Look in any management casebook. No human mind can contain more than
three alternatives. No document should be more than one page long.
Work on your golf handicap.
Say, in Ch. 5, they're trying to explain the trivial concept
of "enthalpy" (fucking mouthfilling word for an obvious
concept, no wonder those here are so prone to shoot names at
us).
Idiot. Do you want the three syllables of "entropy" or economics'
"heteroskedasticity" which can be misspelled with a "c" rather than a
"k" and still be recursively OK?
Google
heteroskedasticity 116,000 hits
heteroscedasticity 101,000 hits
There's convention about it, and there's logic, and
there's of course English language. Three independent
constructions, yet all involved in explaining the subject to
others. They can't hack it! They can't put all three
together.
So sad. Are ya gonna use classical thermodynamic entropy, statistical
thermodynamic entropy, or information theory entropy re Claude
Shannon? That's three. Any more would hopelessly confound you.
Somewhere else, they combine two solids that after reaction
yield some water in which the products proceed to dissolve,
The second and final step in Schroeder's brilliant synthesis of
bullvalene extruded benzene, thus recrystallizing the product from its
own byproduct. Today, the EPA would gut the kraut ***** for having
benzene in the lab and Officially endangering children.
then their treatment of the problem turnes out to be one
that considers water the solvent and not part of the
reaction. Who are these bozos? They've even included a
picture of themselves in the text, all four.
You being a sand *****, why don't you circulate a strongly worded
petition demanding that graven images be removed from the textbook?
What does Allah have to say about holograms, or a text listing of the
jpeg code? In fact, were I you I'd get into a major ethnic linguistic
tizzy about "al cohol" and "al dehyde." Toss in "al gebra," too, and
the Christian translative confabulation that resulted in the trig
function being called "sine."
There are a zillion chemsitry books in the market. It's as
disgusting as Google. Try to find the most obvious type of
information, but one that resides adjacent to a
universe-full of crap for the laymen. See if Google gets you
there.
Do you have any idea how many issues of "Boobs, Busts, and Bazooms,"
"Heels and Garters," or "Shaved Asians" $(US)116 would purchase?
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz.pdf
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| User: "Sbharris[atsign]ix.netcom.com" |
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| Title: Re: Chemists! |
13 Mar 2005 07:05:49 PM |
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Say, in Ch. 5, they're trying to explain the trivial concept
of "enthalpy" (fucking mouthfilling word for an obvious
concept, no wonder those here are so prone to shoot names at
us).
COMMENT:
If you think ethalpy is a trivial concept, it's quite likely you
haven't understood it. But go ahead, make my day. Define "ethalpy" AND
then tell us why the entity with this definition is useful, and used,
in chemistry.
Ready, set, go.
SBH
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| User: "Gregory L. Hansen" |
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| Title: Re: Chemists! |
13 Mar 2005 08:54:42 PM |
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In article <1110762349.392787.183530@z14g2000cwz.googlegroups.com>,
Sbharris[atsign]ix.netcom.com <sbharris@ix.netcom.com> wrote:
Say, in Ch. 5, they're trying to explain the trivial concept
of "enthalpy" (fucking mouthfilling word for an obvious
concept, no wonder those here are so prone to shoot names at
us).
COMMENT:
If you think ethalpy is a trivial concept, it's quite likely you
haven't understood it. But go ahead, make my day. Define "ethalpy" AND
then tell us why the entity with this definition is useful, and used,
in chemistry.
Ready, set, go.
SBH
It's used because chemical reactions are often done in open vessels in
air? And because we care about pressure changes inside engines?
--
"Not that there's anything wrong with just lying around on your back. In
its way, rotting is interesing too... It's just that there are other ways
to spend your time as a cadaver." -- Mary Roach, "Stiff", 2003.
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| User: "Sbharris[atsign]ix.netcom.com" |
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| Title: Re: Chemists! |
13 Mar 2005 09:26:10 PM |
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Basically, yes. It's to remind you that the energy change in a reaction
doesn't always appear as heat. Just for starters you first have to
account for pressure-volume work, and there's even the stress-energy
that results when you change pressure on a constant volume.
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| User: "Maleki" |
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| Title: Re: Chemists! |
14 Mar 2005 12:38:51 PM |
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On 13 Mar 2005 19:26:10 -0800, Sbharris[atsign]ix.netcom.com
wrote:
Basically, yes. It's to remind you that the energy change in a reaction
doesn't always appear as heat. Just for starters you first have to
account for pressure-volume work, and there's even the stress-energy
that results when you change pressure on a constant volume.
Wow! "BFD" (as Uncle Al puts it). If physics was written
like this you'd need a thick dictionary by yourself to look
at everytime you read a sentence; 95 percent of the
definitions totally redundant.
--
"neshasteh khAyeh gondeh mikoneh."
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| User: "Maleki" |
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| Title: Re: Chemists! |
14 Mar 2005 01:35:13 PM |
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On 13 Mar 2005 17:05:49 -0800, Sbharris[atsign]ix.netcom.com
wrote:
Say, in Ch. 5, they're trying to explain the trivial concept
of "enthalpy" (fucking mouthfilling word for an obvious
concept, no wonder those here are so prone to shoot names at
us).
COMMENT:
If you think ethalpy is a trivial concept, it's quite likely you
haven't understood it. But go ahead, make my day. Define "ethalpy" AND
then tell us why the entity with this definition is useful, and used,
in chemistry.
Instead of talking about enthalpy itself I'll push back
to the original subject explaining how _they_ handled
the simplest explanations involved. It's of course tiny
exceptions in the text that I point at, but ones saying a
lot about the authors.
After defining "w" as the work done on the system by
the surroundings, on page 163 they proceed to discuss
reactions under constant pressure conditions and write:
"When the pressure is constant, pressure-volume work
is given by
w = -Pdel(V)
where del(V) is the change in volume. When the
change in volume is positive, the work done by the
system is negative. That is, work is done _by_ the
system _on_ the surroundings."
AS simply as that. Do you see where they missed? (Jee I hope
so)
--
"nafahmidim nazr dAsht yA kaffAreh."
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| User: "Sbharris[atsign]ix.netcom.com" |
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| Title: Re: Chemists! |
15 Mar 2005 03:52:58 PM |
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So long as deltaV is defined as Vfinal - Vinitial, it seems fine to me.
That will be positive if the system expands, and that means the system
is doing work on the surroundings. Which will come out as a negative w
by their definition, due to the minus sign in front of the equation.
Of course, it really doesn't matter if you define w as being a negative
quantity if the system does work (as here) or negative if the system
has work done on it. So long as you are consistant about everything
else.
SBH
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| User: "Maleki" |
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| Title: Re: Chemists! |
15 Mar 2005 06:11:27 PM |
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On 15 Mar 2005 13:52:58 -0800, Sbharris[atsign]ix.netcom.com
wrote:
So long as deltaV is defined as Vfinal - Vinitial, it seems fine to me.
That will be positive if the system expands, and that means the system
is doing work on the surroundings. Which will come out as a negative w
by their definition, due to the minus sign in front of the equation.
Of course, it really doesn't matter if you define w as being a negative
quantity if the system does work (as here) or negative if the system
has work done on it. So long as you are consistant about everything
else.
SBH
I see, this must be why they missed it through nine
editions. You're a credit for them. That is, if you make
that mistake and _could_ make that mistake, then I accept if
they did same. I consider you a good scientist.
But then there are four of them and you're just one. That's
four times nine. Damn...
--
"folAni shAkhesh shekast!"
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| User: "Sbharris[atsign]ix.netcom.com" |
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| Title: Re: Chemists! |
15 Mar 2005 09:13:02 PM |
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Are you saying they *didn't* define deltaV as Vfinal--Vinitial? That is
the usual way it's defined, and if it is, I see no mistake in anything
they say.
In short, what's your problem?
.
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| User: "Maleki" |
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| Title: Re: Chemists! |
15 Mar 2005 10:37:08 PM |
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On 15 Mar 2005 19:13:02 -0800,
Sbharris[atsign]ix.netcom.com wrote:
Are you saying they *didn't* define deltaV as Vfinal--Vinitial? That is
the usual way it's defined, and if it is, I see no mistake in anything
they say.
In short, what's your problem?
Del(V) is defined OK, as is usually done. But they've
made a logical error elsewhere in what I quoted from
them. Read it carefully just once. Somebody read this
carefully just once for god's sake!
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| User: "Sbharris[atsign]ix.netcom.com" |
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| Title: Re: Chemists! |
15 Mar 2005 10:49:25 PM |
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I read it carefully and find nothing wrong with it. Perhaps if you can
bring yourself to quoting the single sentence that gives you problem?
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| User: "Maleki" |
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| Title: Re: Chemists! |
15 Mar 2005 11:21:17 PM |
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On 15 Mar 2005 20:49:25 -0800,
Sbharris[atsign]ix.netcom.com wrote:
I read it carefully and find nothing wrong with it. Perhaps if you can
bring yourself to quoting the single sentence that gives you problem?
With the risk of having been _bamboozled_ of course, I
go ahead and quote that sentence:
"When the change in volume is positive, the work
done by the system is negative."
It would be interesting if you would at least briefly
explain why you or others could miss this. Cause at
this point I'm just clueless.
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| User: "David Cross" |
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| Title: Re: Chemists! |
15 Mar 2005 11:37:59 PM |
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"Maleki" <maleki_m_@hotmail.com> wrote in message
news:bpl1l1ka7por.1634dwi65iq2b$.dlg@40tude.net...
On 15 Mar 2005 20:49:25 -0800,
Sbharris[atsign]ix.netcom.com wrote:
I read it carefully and find nothing wrong with it. Perhaps if you can
bring yourself to quoting the single sentence that gives you problem?
With the risk of having been _bamboozled_ of course, I
go ahead and quote that sentence:
"When the change in volume is positive, the work
done by the system is negative."
It would be interesting if you would at least briefly
explain why you or others could miss this. Cause at
this point I'm just clueless.
Well, work is defined as - integral P dV , so going to the approximative case
where the pressure is constant, it looks like this:
W = - P * (delta-V)
Thus when delta-V is positive the work is negative. Badum-kish.
The physical significance of this is easy to see if you look at a piston
inside a cylinder. If the piston rises, the volume of the gas has gone up, and
so the gas has done work on the piston (i.e. work has been done BY the system
ON the surroundings) and by convention this is negative in opposition to heat
flow, since Q(in) is positive in this case.
--
David Cross
dcross1 AT shaw DOT ca
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| User: "Maleki" |
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| Title: Re: Chemists! |
16 Mar 2005 08:57:42 AM |
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On Wed, 16 Mar 2005 05:37:59 GMT, David Cross wrote:
W = - P * (delta-V)
Thus when delta-V is positive the work is negative. Badum-kish.
When "work is negative" (by the convention used), work done
by the system is not negative. Pull your head out, please.
--
"dosad man ostekhAn bAyad ke sad man bAr bardArad"
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| User: "Sbharris[atsign]ix.netcom.com" |
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| Title: Re: Chemists! |
16 Mar 2005 08:58:59 PM |
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When the change in volume is positive, the work
done by the system is negative <<
Yeah, by golly, you're right. This should read "the work done ON the
system is negative." Otherwise, it all looks fine if you make that one
change.
As to why this is difficult to spot, well, it's easy to get signs
screwed up. If work ON the system is positive, then work done BY the
system is negative. And work done ON the system always has the opposite
sign of work done ON the environment. And work done BY the system has
the opposite sign of work done BY the environment.
SBH
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| User: "David Cross" |
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| Title: Re: Chemists! |
16 Mar 2005 10:04:50 PM |
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"Sbharris[atsign]ix.netcom.com" <sbharris@ix.netcom.com> wrote in message
news:1111028339.260314.177810@g14g2000cwa.googlegroups.com...
When the change in volume is positive, the work
done by the system is negative <<
Yeah, by golly, you're right. This should read "the work done ON the
system is negative." Otherwise, it all looks fine if you make that one
change.
As to why this is difficult to spot, well, it's easy to get signs
screwed up. If work ON the system is positive, then work done BY the
system is negative. And work done ON the system always has the opposite
sign of work done ON the environment. And work done BY the system has
the opposite sign of work done BY the environment.
My experience has been that sign conventions occasionally differ across PChem
texts for reasons not clear to me. That having been said, I will gladly mea
culpa in this case. :)
--
David Cross
dcross1 AT shaw DOT ca
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| User: "Maleki" |
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| Title: Re: Chemists! |
17 Mar 2005 08:15:11 AM |
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On 16 Mar 2005 18:58:59 -0800, Sbharris[atsign]ix.netcom.com
wrote:
When the change in volume is positive, the work
done by the system is negative <<
Yeah, by golly, you're right. This should read "the work done ON the
system is negative." Otherwise, it all looks fine if you make that one
change.
Now that's a good scientist :) Ever ready to acknowledge
even tiniest mistakes, and doing it with no qualms.
I just had a similar talk with the woman I'm with last
night. She was telling me that in her whole life she had not
seen any man, including her father (and past husbands!),
apologizing to her, until she met me. And I was explaining
to her that the important thing for someone having lived
like me is always _finding_ the mistake and not whose it
was, therefore after the main job is done then acknowledging
whose it was is a tiny and trivial thing on the side.
Anyway, the point, the original point was that the text has
things like this here and there throughout the chapters. And
this is the ninth edition of the text with four different
chemists working on it. I don't think this is permissible.
--
"dami bA gham besar bordan jahAn yeksar nemi'arzad
be mey befrush dalghe mA kazin behtar nemi'arzad
cheh AsAn minemud avval ghame daryA be buye sud
ghalat kardam ke'in tufAn besad gowhar nemi'arzad
cho hAfez dar ghanA'at kusho az donyAye dun bogzar
keyek jow mennate dunAn dosad man zar nemi'arzad"
- Hafez
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| User: "Maleki" |
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| Title: Re: Chemists! |
11 Mar 2005 09:33:11 AM |
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On Thu, 10 Mar 2005 11:03:01 -0800, Uncle Al wrote:
You being a sand *****, why don't you circulate a strongly worded
petition demanding that graven images be removed from the textbook?
What does Allah have to say about holograms, or a text listing of the
jpeg code? In fact, were I you I'd get into a major ethnic linguistic
tizzy about "al cohol" and "al dehyde." Toss in "al gebra," too, and
My frustration has to do with something that's got nothing
to do with me. I'm pissied that there are opportunities for
people to choose the path of even writing a chemistry book
so that they could pay their fucking mortgages. It's
everywhere in USA. Singers sing, authors write, "artists"
create, "scientists" slave, and crooks cheat, ALL for the
sole purpose of paying their mortgages :-(
Every crook advises his son, "well son, you didn't get much
education plus you're obviously already an alcoholic and use
drugs too but you can always give another look to the vacuum
cleaner we build here and sell it as another marvelous
innovation in vacuum cleaning technique."
"Herbs! Diet pills. A chemistry text! Go for it son. It'll
take care of you."
--
"rAhe dozdzadeh tA chehel ruz amneh."
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| User: "Mark Fergerson" |
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| Title: Re: Chemists! |
12 Mar 2005 03:51:23 PM |
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Maleki wrote:
On Thu, 10 Mar 2005 11:03:01 -0800, Uncle Al wrote:
You being a sand *****, why don't you circulate a strongly worded
petition demanding that graven images be removed from the textbook?
What does Allah have to say about holograms, or a text listing of the
jpeg code? In fact, were I you I'd get into a major ethnic linguistic
tizzy about "al cohol" and "al dehyde." Toss in "al gebra," too, and
My frustration has to do with something that's got nothing
to do with me. I'm pissied that there are opportunities for
people to choose the path of even writing a chemistry book
so that they could pay their fucking mortgages. It's
everywhere in USA. Singers sing, authors write, "artists"
create, "scientists" slave, and crooks cheat, ALL for the
sole purpose of paying their mortgages :-(
Every crook advises his son, "well son, you didn't get much
education plus you're obviously already an alcoholic and use
drugs too but you can always give another look to the vacuum
cleaner we build here and sell it as another marvelous
innovation in vacuum cleaning technique."
"Herbs! Diet pills. A chemistry text! Go for it son. It'll
take care of you."
It must be a Sign of The Apocalypse; Maleki and Uncle Al have found a
point of agreement.
Mark L. Fergerson
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| User: "Uncle Al" |
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| Title: Re: Chemists! |
12 Mar 2005 05:43:06 PM |
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Mark Fergerson wrote:
Maleki wrote:
On Thu, 10 Mar 2005 11:03:01 -0800, Uncle Al wrote:
You being a sand *****, why don't you circulate a strongly worded
petition demanding that graven images be removed from the textbook?
What does Allah have to say about holograms, or a text listing of the
jpeg code? In fact, were I you I'd get into a major ethnic linguistic
tizzy about "al cohol" and "al dehyde." Toss in "al gebra," too, and
My frustration has to do with something that's got nothing
to do with me. I'm pissied that there are opportunities for
people to choose the path of even writing a chemistry book
so that they could pay their fucking mortgages. It's
everywhere in USA. Singers sing, authors write, "artists"
create, "scientists" slave, and crooks cheat, ALL for the
sole purpose of paying their mortgages :-(
Every crook advises his son, "well son, you didn't get much
education plus you're obviously already an alcoholic and use
drugs too but you can always give another look to the vacuum
cleaner we build here and sell it as another marvelous
innovation in vacuum cleaning technique."
"Herbs! Diet pills. A chemistry text! Go for it son. It'll
take care of you."
It must be a Sign of The Apocalypse; Maleki and Uncle Al have found a
point of agreement.
He's learned to be offensive at a target deserving of disgust. One
sign of adulthood is realizing that you are being screwed. A second
sign is to go out and do some screwing of your own. The young are
ever ripe for plucking.
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz.pdf
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