Worked example

  • Given stock solution of 5mg/cm(3)

  • Want 20cm(3) of a 2mg/cm(3) solution

concentration wanted/concentration got

times

volume wanted

equals

vol. of stock solution you need to take

so

2/5 × 20 = 8

so take 8cm(3) of stock solution and make it up to 20 using 12cm(3) of distilled water

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