PI Industries Quality Control Chemist QC Chemist Interview Questions, Process, and Tips

Internal and external standards are used in quality control to ensure accurate and reliable measurements.

• Internal standard is a substance that is added to the sample being analyzed, which is used as a reference to measure the analyte of interest.

• External standard is a separate sample with a known concentration of the analyte, which is used to calibrate the instrument and validate the accuracy of the measurements.

• Intern...read more

To prepare a solution, measure the required amount of solute and dissolve it in the appropriate amount of solvent.

• Determine the concentration and volume of the desired solution

• Measure the required amount of solute using a balance

• Add the solute to a volumetric flask or beaker

• Add the appropriate amount of solvent to reach the desired volume

• Stir the solution until the solute is completely dissolved

Instruments are calibrated by comparing their readings to a known standard and adjusting them accordingly.

• Identify the standard to be used for calibration

• Ensure the instrument is clean and free of debris

• Record the initial readings of the instrument

• Compare the readings to the standard and adjust as necessary

• Record the final readings and document the calibration process

Primary standards are highly pure compounds used for calibration, while secondary standards are less pure and used for routine analysis.

• Primary standards are used to calibrate instruments and determine the accuracy of measurements.

• They are highly pure and stable compounds that can be weighed accurately.

• Examples of primary standards include potassium hydrogen phthalate and sodium carbonate.

• Secondary standards are used f...read more