Analytical chemistry lab?
How do you prepare 50ml 100mg/ml caffeine stok solution and 50 ml 1mg/ml Gallic acid stok solution from pure standards?(Gallic acid Mwt:170g/mol and caffeine Mwt:194g/mol)
- 3 months agoFavorite Answer
The Mwt of the compounds does not enter into the calculations because you are not calculating molarity or using molar mass in any way.
(a). 50 ml of 100 mg/ml caffeine.
50 ml x 100 mg/ml = 5000 mg caffeine. Weigh out 5000 mg (5 g) caffeine and dissolve in water to make a final volume of 50 ml.
(b). 50 ml of 1 mg/ml gallic acid.
50 ml x 1 mg/ml = 50 mg. Weigh out 50 mg of gallic acid and dissolve in water to make a final volume of 50 ml.