2.3 Place container with sample in the vacuum oven to 60-70°C < 25 mm Hg for 5-6
hours.
2.4 Transfer the container with the dried sample into a desiccator, cool for 30 min
and weigh (W3). Repeat the heating procedure until constant weight is obtained. Different in
weight between two consecutive weighing should not be more than 5mg.
2.5 Calculation