Question

The crucible is not fired, as the procedure suggests, but had 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 the experiment. Will the mass of final product be too high, too low, or unchanged as a rsult of this technique error? Explain

Answer 1

We are given a crucible that essentially dirty because of the oil smudges from fingers and some impurities. During the experiment, the crucible is fired off which removes volatile impurities such as water and other substances that evaporate under the indicated temperature of burning. Thus the weight of the crucible decreases.