Basic question

Martin Houle martin.houle at REMOVE.drs.crchul.ulaval.ca
Thu Mar 18 13:58:48 EST 1999


In article <199903181651.JAA61260 at nestor.NMSU.Edu>, hroychow at NMSU.EDU
("Hiranya S. Roychowdhury") wrote:

> At 11:04 PM 3/17/99 -0600, Jesse J. Parry wrote:
> >
> >Dima Klenchin <klenchin at facstaff.REMOVE_TO_REPLY.wisc.edu> wrote in message
> >news:7c66it$fve$2 at news.doit.wisc.edu...
> >>:SInce no one seems inclined to answer your question, I will.
> >>
> >>Hmm, a number of people did provide the answer.
> >>
> >>>However, I
> >>:would recommend that you find this type of answer in a textbook as it
> >>:should be very easy to find.
> >>:
> >>:a mol is equivalent to 6.02E23 molecules.
> >>
> >>I disagree. ;-)
> >>
> >>A mole is a measure of quantity defined in such way as to compare absolute
> >>number of single molecular entities of having different molecular masses.
> >>Arbitrary, it was taken to be measured in grams (number of them
> >>equal to the molecular mass). It *happened* (by the design of the our
> >>universe) that every mol contains ~ 6.02^23 molecules (called Avogadro's
> >>number - the arbitrary nature of which is clear from the fact
> >>that it is not whole number, if I remember it correctly).
> >>
> >>IMHO, this way of putting it is more logical.
> >>
> >>:therefore a mmol is equivalent to 6.02E20 molecules.
> >>:it refers to an absolute number of molecules.
> >>:
> >>:on the other hand, M corresponds to a concentration. That is 6.02E23
> >>:molecules per liter.
> >>:
> >>:therefore a mM concentration is equivalent to 6.02E20 molecules per liter.
> >>:
> >>
> >>Naturally, there is nothing to add here.
> >>
> >>        - Dima
> >
> >How about a reference for this information that you obviously pulled out of
> >a text and not your head......right.
> 
> This is really outrageous! You NEED a REFERENCE for the information? 
> 
> As you yourself pointed out, it comes from a text book. However, I'm almost
> sure that some of us do not have to open this basic "text book" to explain
> the relationships between "mole" "molar" "Avogdrao's number" and "molar
> equivalent". 
> But, if you must have it... just grab any basic (inorganic) chemistry text
> book and go through the chapters on physical chemistry, molecules etc.
> 
> 
> Dr. Hiranya Sankar Roychowdhury
> GENE LAB/ EPPWS
> New Mexico State University
> Las Cruces, NM 88003
> Ph. (505) 646-5785
> hroychow at nmsu.edu

I suggested that the person who originally asked the question LOOK IN A
TEXTBOOK BEFORE HE BOTHERS US IN THIS NEWSGROUP not that I need a textbook
for the answer. I Guess that'll teach me to try and be nice and answer a
question.

The only mistake I did here was use the word absolute, which indeed does
not belong there but still I beleive the information I provided clearly
distinguished the difference between the two units of measere. That is
that one is a quantity and the other a concentration. 

Why do I even bother to reply? 

Instead of complaining you should have answered the damn post to begin with.

Martin Houle



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