Answer :
The most reasonable step to take will be to check the calibration of the
thermometer to ensure that it is giving accurate readings.
Experiments which are done to be give the same results under standard
conditions. Common causes of incorrect results during the analysis of
boiling point of substances include heating the substance too rapidly or
the thermometer not being properly calibrated.
The thermometer is used to measure the temperature and so must be
properly calibrated to give accurate readings.
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