All chromatographic methods have in common the use of a ______ phase and a______ phase.

All chromatographic methods have in common the use of a stationary phase and a mobile phase.

2. Which of the following methods is not commonly used to separate interfering components? ( ) A: Precipitation separation method B: Titration analysis C: Ion exchange method D: Chromatographic separation

If the chromatographic operating conditions are not easily controlled to be unchanged during measurement process, which of the following is the better method to determine the component content() A: normalization method B: external standard method C: internal standard method D: calibration curve method