general chem lab question- the fired crucible is handled with oily fingers after its mass measurement but before the 3 g sample of the hydrated salt...

general chem lab question- the fired crucible is handled with oily fingers after its mass measurement but before the 3 g sample of the hydrated salt is measured. subsequently the oil from the fingers is burned off. how does the technique error affect the report percent water in the hydrated salt? Explainlab 5 percent water in a hydrated salt