kingofnobbys
BD.org Sicko
A wee bit of high school science.
Two point method :
Ground ice mixed with cold tap water , mix and let come to equilibrium by standing for 10mins , give it a stir and take the reading by immersing the probe in the ice-water mix , should read 0 degC.
Bring water to a rolling boil , and immerse probe in the boiling water , should read 100 degC.
If both are spot on , assume a straight line between two points and any measurement in the range 0 - 100 degC will be accurate.
If one or both are out, it's an issue with the thermometer, again draw a straight line between the high and low reading and note the varying differences between line and a line drawn between the standard temperatures , this gives the error and allows you to correct for any measured temperature between the high and low.
Calibration Curve Method :
Requires 3 or more KNOWN temperatures plotted as curve.
Need at least one other pure substance with a bp or mp in the range required , best if it's bp or mp is close to the desired temperature.
Use a spline to fit a curve between the H20 mp, material 2 temp, material 3 temp ...., and H20 bp.
Now measure these temperatures and draw a second curve , the difference is the error curve.
Convenient melting points (mp) in degrees C
H20 = 0.0
S = 95.3
K = 63.5
Glycerol = 20.0
Naphthalene = 80.3
Benzoic Anhydride = 42.0
Phenol = 40.9
Convenient boiling points (bp) in degrees C
H20 = 100.0
Acetaldehyde = 20.4
Acetone = 56.3
CS2 = 46.5
Methy Acetate = 56.3
Methyl Formate = 31.5
Iodo Methane = 43.4
Two point method :
Ground ice mixed with cold tap water , mix and let come to equilibrium by standing for 10mins , give it a stir and take the reading by immersing the probe in the ice-water mix , should read 0 degC.
Bring water to a rolling boil , and immerse probe in the boiling water , should read 100 degC.
If both are spot on , assume a straight line between two points and any measurement in the range 0 - 100 degC will be accurate.
If one or both are out, it's an issue with the thermometer, again draw a straight line between the high and low reading and note the varying differences between line and a line drawn between the standard temperatures , this gives the error and allows you to correct for any measured temperature between the high and low.
Calibration Curve Method :
Requires 3 or more KNOWN temperatures plotted as curve.
Need at least one other pure substance with a bp or mp in the range required , best if it's bp or mp is close to the desired temperature.
Use a spline to fit a curve between the H20 mp, material 2 temp, material 3 temp ...., and H20 bp.
Now measure these temperatures and draw a second curve , the difference is the error curve.
Convenient melting points (mp) in degrees C
H20 = 0.0
S = 95.3
K = 63.5
Glycerol = 20.0
Naphthalene = 80.3
Benzoic Anhydride = 42.0
Phenol = 40.9
Convenient boiling points (bp) in degrees C
H20 = 100.0
Acetaldehyde = 20.4
Acetone = 56.3
CS2 = 46.5
Methy Acetate = 56.3
Methyl Formate = 31.5
Iodo Methane = 43.4
