Question

The crucible is not fired, as the procedure suggests, but has retained some impurities from previous use (or it could be oily smudges from fingers). The mass of the dirty crucible is recorded. However the impurities are burned off in the experiment. Will the reported mass of the final product be too high , too low , or Unchanged as a result of this technique error?

Answer 1

If there are impurities, this usually heightens the mass, since you're adding more particles onto the thing.