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)

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  • 1 month ago
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    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.

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