Here's a protocol that might accomplish the pedagogic aims,
visualization liquid CO2, without the grandstanding, kabooms.
*****
From ESCUDERO_E@HCCAI.HCCA.OHIO.GOVSat Feb 17 00:10:32 1996
Date: Fri, 16 Feb 1996 16:38:37 -0500
From: Edmund Escudero <ESCUDERO_E@HCCAI.HCCA.OHIO.GOV>
Reply to: Chemistry Education Discussion List <CHEMED-L@UWF.BITNET>
To: Multiple recipients of list CHEMED-L <CHEMED-L@UWF.BITNET>
Subject: Re: Boiling Point and Sublimation
I have performed a similar demo by cutting off the tip of a jumbo size
beral pipet, crushing some dry ice and scooping the dry ice snow into
the beral. After filling the beral 1/3 full of dry ice, fold over the
stem and clamp the folded end closed with a pair of pliers. After a
short while the solid CO2 in the pipet turns to a liquid. As a result,
it is possible to actually see liquid CO2. Releasing the pressure by
loosening the grip on the pliers produces instant snow in the pipet.
Be sure to observe all of the necessary precautions. I have had a pipet
split along the seam. I believe Bob Becker may have been the person who
demonstrated this.
In the mid-80's while I was teaching in Houston, some 14/15 year old
kids but dry into a glass Perrier type bottle and handed the bottle to
a younger boy. The bottle exploded in the boys hand. He was
critically injured and survived because of the immediate care he
received from the many doctors/surgeons who were attending the River
Oaks Tennis tournament where the accident occurred.
Edmund J. Escudero
Chemistry Instructor/Chair Science Dept.
Summit Country Day School school phone (513) 533-5400
2161 Grandin Rd. School FAX (513) 533-5373
Cincinnati, OH 45208-3300 home phone (513) 231-6157
e-mail escudero_e@hcca.ohio.gov
*********
John N. Cooper, Chemistry
Bucknell University
Lewisburg PA 17837-2005
jcooper@bucknell.edu http://www.facstaff.bucknell.edu/jcooper
VOX 570-577-3673 FAX 570-577-1739