A 0.484g sample of impure NH4Br is treated with 25.00 mL of 0.2050 M NaOH and heated to drive off NH3. The unreached NaOH in the reaction mixture after heating required 9.95 mL of 0.0525 M H2C2O4 to neutralize.
How many grams of NH4Br were in the original sample, and what is the percentage NH4Br in the original sample?