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Re: [Phys-l] Boiling Point of water - a mystery?

This comment assumes that the students have been brought up in a Fahrenheit culture.
If in fact they are far more comfortable with Celcius - then my thoughts are totally out of order.

My suspicion is that the thermometers are marked with a longer mark every ten degrees.
The student(s?) were unconsciously 'expecting' the B.P. to be 212 and inadvertently misread the mark. Recording 112 instead of the actual 102.

At 3:11 PM -0500 1/11/10, Fakhruddin, Hasan wrote:
This was forwarded from chem list-serv; I thought we physics folks would be equally interested in it.


1. A query from a science teacher:
I am an 8th grade science teacher, and we recently did an activity in which the students collected temperature data as they heated ice to go through phase changes. As expected, they had plateaus for melting and boiling points, but one group in particular had a mystery that we can't yet solve.

At one lab station, the "boiling point" was much higher than any other station. In each class, the plateau was around 112 degrees C, while most other station recorded boiling points around 101 or 102 C. Our first guess was that the thermometer they were using (a simple glass/alcohol one) was not calibrated properly,