The percentage of water in an unknown hydrated salt is to bedetermined by weighing a sample of the salt, heating it to driveoff water, cooling it to room temperature, and re-weighing. whichprocedural mistake would result in determining a percentage ofwater that is too low?
procedural mistakes

i. heating the sample in aclosed, rather than an open, container
ii. re-weighing thesample before it has cooled to room temperature

a. i only
b. ii only
c. both i andii
d. neither i norii