Path: csiph.com!usenet.pasdenom.info!aioe.org!news.swapon.de!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail From: Gregory Ewing Newsgroups: comp.lang.python Subject: Re: .split() Qeustion Date: Sun, 18 Aug 2013 11:30:14 +1200 Lines: 21 Message-ID: References: <94f8428f-50b9-4ccd-95a0-6eeafda0fe18@googlegroups.com> <1376499950.3355.9802231.6A03F40D@webmail.messagingengine.com> <98e36bd1-1115-4f1d-b535-171f47408a62@googlegroups.com> <87siybuii8.fsf@nautilus.nautilus> <520CEB96.2050902@mrabarnett.plus.com> <87mwojug2i.fsf@nautilus.nautilus> <520da6d1$0$30000$c3e8da3$5496439d@news.astraweb.com> <2d88bc0f-fdcb-4685-87ed-c17998dd3137@googlegroups.com> <8584caa1-1593-41ac-8e0c-4ac4639913d6@googlegroups.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Trace: individual.net y/zhU/AIaRnBMmmQDJFqYgnuK/IQS+j43E0dm8NRNWw1PVGmcs Cancel-Lock: sha1:53+5SAVpkYygEAHzSMFIUi4xqTE= User-Agent: Mozilla Thunderbird 1.0.5 (Macintosh/20050711) X-Accept-Language: en-us, en In-Reply-To: <8584caa1-1593-41ac-8e0c-4ac4639913d6@googlegroups.com> Xref: csiph.com comp.lang.python:52645 wxjmfauth@gmail.com wrote: > Na + Cl --> NaCl > > the chemist combines *one mole* of sodium and *one > mole* of chlorine to get *one mole* of sodium chloride > > It's independent of the number of "particles" in a mole. The actual number chosen for the unit is arbitrary, but number of particles is still the central issue. The important thing is to have the *same* number of particles of Na and Cl. Weight only comes into it because it's totally impractical to count particles. And the particular number 6.02e23 is chosen because it happens to give a convenient relationship between number of particles and grams. If chemists had decided to use ounces instead, the number would be different. -- Greg