A niacin vitamin tablet specifies that each tablet contains 100 mg nicotinic acid. A student looking for extra credit in general chemistry lab asks the instructor if it is OK if the vitamin tablet is titrated to determine if the amount the manufacturer claims to be there is correct. Two tablets are crushed and combined, and together weigh 0.3813 g, and require 18.80 mL of 0.1000 M NaOH to titrate to the equivalence point.
The ingredients list on the bottle indicates that dicalcium phosphate, microcrystalline cellulose, modified cellulose gum, magnesium stearate, stearic acid and calcium silicate are present. Would the experimental percent nicotinic acid be too high, too low, unaffected, or can't be determined?