Question

A method for the determination of boric acid in a solution for the production of eye...

A method for the determination of boric acid in a solution for the production of eye drops gave 3.0 ± 0.17 mg mL-1 boric acid. From this information it follows that this is the number of samples that need to be anlyzed to ensure 4% RSD.

6 samples

8 samples

10 samples

None of the above

Homework Answers

Answer #1

3 0.17

RSD=.     = 4

4= / 3 *100

= 0.12

margin of error = Z *

for 99.99% Z = 3.891

so we have

= 0.46692/0.17

   = 2.746589

n = 7.54

so n = 8 i.e. 8 samples Answer

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