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Practice Questions
Test your understanding with targeted questions related to the topic.
Question 1
Easy
What is a surrogate?
💡 Hint: Think about what similar means in this context.
Question 2
Easy
Why do we use hexane in extraction?
💡 Hint: Consider the polarity of hexane.
Practice 4 more questions and get performance evaluation
Interactive Quizzes
Engage in quick quizzes to reinforce what you've learned and check your comprehension.
Question 1
What is the purpose of adding a surrogate to a sample?
- To dilute the sample
- To optimize extraction methods
- To measure recovery efficiency
💡 Hint: Think about what you can use to compare.
Question 2
True or False: The recovery rate must always be above 100%.
- True
- False
💡 Hint: Consider the definition of recovery.
Solve 2 more questions and get performance evaluation
Challenge Problems
Push your limits with challenges.
Question 1
After adding 0.1 mg of a surrogate to your sample and obtaining a recovery rate of 80%, calculate the concentration of the surrogate in the original sample.
💡 Hint: Use the recovery formula to trace back to the original concentration.
Question 2
If an instrument response gives a value of 50,000 units for a sample diluted down to 10 mL from original 100 mL, and the calibration factor is 5,000 units/mg, find the concentration of the analyte in the original sample.
💡 Hint: Front-load your calculations properly.
Challenge and get performance evaluation