Resolution of Matter into pure Substances, II. Fractional Crystallization Advanced Study Assignment Trey weighed a 150-mL beaker (67.34 g) and a piece of filter paper (0.34 g) He added his unknown sample to the beaker and reweighed it (97.12 g). What was the mass of Trey's sample? Trey separated the sand from the unknown sample using a Buchner funnel. He washed it and then dried the sample on the filter paper. The resulting mass of the sand on the Filter piper was 5.81 g. What was the mass of sand that Trey recovered from his sample? Calculate the percent sand recovered using the equation below. %Sand=Sand Mass/Sample Mass x 100%