Practice question · True or false
The setting of plaster is exothermic, so a setting block becomes noticeably warm.
Hints
- Recall what happens chemically as plaster sets.
- Rehydration releases heat.
Show the answer
True
Why
True, and it is the most reliable sign that plaster has gone off. The hemihydrate rehydrates to the dihydrate and the reaction releases heat, so a block that is warming is setting, which is more informative than poking it.
Practise Moulds II: Materials and Procedure
The app has 5 more questions on this lesson, and keeps your place in the course. Sculpture I is free to start.
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