Re: pinhole a question on heat

Date view Thread view Subject view Author view Attachment view

From: Steven Eiger (eiger@montana.edu)
Date: Mon May 13 2002 - 08:36:27 PDT 

Message-Id: <l03102807b9058d0e54e9@[153.90.150.107]>
Date: Mon, 13 May 2002 09:36:27 -0600
From: Steven Eiger <eiger@montana.edu>
Subject: Re: pinhole a question on heat

Steve, it is my understanding that it is best to look at these water
molecules as all interacting with one another through hydrogen bonds. Each
molecule has a different amount of kinetic energy; some have sufficient
energy to fly out of the surface, escaping the clutch of their fellow
molecules. This leaves the ones left behind a bit cooler. To ensure that
molecules continue to leave apparently one needs to add 540 cal/Gram.

>Hi everyone -
>
>Here's one of those questions that is so basic, yet I, at least, can't
>answer it.
>
>For water to turn to steam it must absorb 540 calories/gram. This is heat of
>vaporization. But what's going on with the water molecules. Why does it need
>to absorb this heat to vaporize? Are the water molecules adhering - and the
>energy breaks these bonds? What's really going on?
>
>(Ditto question for the phase transition from ice to water)
>
>Thanks for the help,
>
>Steve Miller
>
>

Steven Eiger, Ph.D.

Department of Cell Biology and Neuroscience and the WWAMI Medical Education
Program
PO Box 173148
Montana State University - Bozeman
Bozeman, MT 59717-3148

Voice: (406) 994-5672
E-mail: eiger@montana.edu
FAX: (406) 994-7077

Date view Thread view Subject view Author view Attachment view

This archive was generated by hypermail 2.1.3 : Mon Aug 05 2002 - 09:21:41 PDT