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Technical data


Determination of molar masses via a measurement of the freezing point depression (cryoscopy)

Article no: P3022000
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

Principle

In order to train and demonstrate the determination of molar masses by way of a measurement of the freezing-point depression, urea or hydroquinone are used as test substances. The cryoscopic constant of water is determined from the freezing point depression.

Benefits

  • With detailed experiment guide
  • Compact, easily transportable setup
  • Simultaneous display of current temperature and temperature difference

Tasks

  1. Determine the freezing point depression of water dissolving different amounts of hydroquinone and urea.
  2. Calculate the cryoscopic constant from the experimental results.

Learning objectives

  • Cryoscopic constant
  • Freezing point depression
  • Molar mass

Necessary accessories

  • Precision balance 620g/0.001g

 


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