IUBio

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



More information about the Methods mailing list

Send comments to us at biosci-help [At] net.bio.net