Dear Asghar,

I hope I understand your question correctly.

I would like to suggest the following calculation:

You would like to determine the arsenic content (mg/kg) of a solid sample.

1) 0.25 g sample were digested in a final volume of 50 mL

2) Analysis of the solution: 0.07 µg/mL As

3) Total arsenic: 0.07 µg/mL x 50 mL = 3.5 µg As

4) Arsenic content of the sample: 3.5 µg / 0.25 g = 14 µg/g (= 14 mg/kg)

Best regards

Carsten

Thank You Dr. Carsten Bahr for your guidance and support