Parr Instrument 6725 - Manual (Page 39)

6725
Semi-micro Calorimeter Instruction Manual
5-12
Calculation Factors Menu
Nitric Acid Factor:
Ratio of the nitric acid correction when the
released energy corresponds to 6318 calories.
The default is 1.58 calories per 1000 calories of
released energy.
Acid Multiplier:
This multiplier is the normality of the sodium
carbonate used to titrate for the acid correction.
The default value of 0.0709 allows for direct
entry of the acid correction in calories. If the
bomb rinses are titrated in order to determine
the acid correction, press this key to display the
Acid Multiplier numeric dialog box, where you can change the multiplier to represent the
concentration of the base (equivalents/L) or normality used for titration. In this case, the
acid correction is entered as milliliters of base used to titrate the bomb rinses.
Sulfur Value is Percent:
When set to ON, the sulfur value is being entered as weight percent sulfur. If another
system is to be used, this must be turned OFF and the sulfur multiplier set accordingly.
Sulfur Multiplier:
Values entered by the user to be used for the sulfur correction are multiplied by this value
to get the product into units of milliequivalents. The default number (0.6238) requires that
the sulfur value be entered in weight percent.
Fuse Multiplier:
The fuse corrections represent the number of calories liberated by the burning fuse wire used
to ignite the sample. If another measurement is used, the correction factor must be entered
here. Press this key to access the Fuse Multiplier numeric dialog box and enter this multiplier
value.
Use Offset Correction (ISO):
The thermochemical calculations used for treatment of nitric acid and sulfuric acid corrections
in the ISO and B. S. methods require an offset correction to compensate for the back titration
that is made. To use these calculations, toggle this to ON and enter the appropriate value as
the offset value.
Offset Value:
The value used when Offset Correction is turned ON. Press this key to access the Offset
Value numeric dialog box and change its value.