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Chapter 5: Q5-22 P (page 116)

Why is it desirable in the method of standard addition to add a small volume of concentrated standard rather than a large volume of dilute standard?

Short Answer

Expert verified

  • The large volume of dilute standard will alter the concentration of the matrix and will possibly result to matrix effect.

  • The addition of diluted standards may also cause a difficulty in detection.

  • The large volume of dilute standard may also affect the sensitivity of the instruments being used.

  • The measurements made will be nearly similar to each other when only a small volume of concentrated standard is added.

Step by step solution

01

Step 1:Concentrated and dilute standard definition

  • A standard solution is a solution that has a precisely known concentration of an element or compound in analytical chemistry.
  • A dilution is a solution that decreases the concentration of a solute by adding additional solvent to a more concentrated solution (stock solution).
02

Key points

There are a couple of reasons why it is desirable to add only a small volume of concentrated standard rather than a large volume of dilute standard:

  • The large volume of dilute standard will alter the concentration of the matrix and will possibly result to matrix effect.

  • The addition of diluted standards may also cause a difficulty in detection.

  • The large volume of dilute standard may also affect the sensitivity of the instruments being used.

  • The measurements made will be nearly similar to each other when only a small volume of concentrated standard is added.

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