1. What weight of acetaminophen is required to make a 0.1 M stock solution in 50 mL of 0.05 M perchloric acid?

2. What mass of sodium chloride is required to make a 1 L 500 ppm stock solution of the chloride ion?

3. What volume of 2% (w/v) ethylenediamine should be added to a 300 ppm (1 L) Ni solution to give a 2:1 mole ratio of ethylenediamine to nickel?

4. The following absorbance values were recorded for a blank solution. Calculate the LOQ, to three decimal places.

0.003

0.012

0.017

0.017

0.016