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

The author indicated that it was only the one apparatus used that had the consistent result of 112 C in
multple classes (different students). The only reported difference was the strength of the burner, but I
suppose they could have switched that out to test whether that made a difference.

On 11 Jan 2010 at 15:27, chuck britton wrote:

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,
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