Normally I get help from Cramster but they don't have my analytical book... Our teacher explained it wrong so I have no idea how to do it correctly...

A carbonate fusion was need to free the Bi fro a .6423g sample containing the mineral eulytite (2Bi2O3 3SiO2). The fused mass was dissolved in a dilute acid, following which the Bi3+(3+ ion) was titrated with 27.36 mL of .03369M NaH2PO4. The reaction is Bi3+ + H2PO4- -> BiPO4(s) +2H+

Calculate the percent purity of eulytite (1112 g/mol) in the sample.

He said the answer is about 40... any help would be great... a new teacher would even be great
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