Question

what is the purpose of the applied electric field in mass spectrometry? to repel the ions to accelerate the ions to change the color of the ions to cool down the ions

Explanation:

In mass - spectrometry, an electric field is used to accelerate ions so that they gain kinetic energy and move at a certain velocity for further separation based on mass - to - charge ratio in the mass analyzer. It is not for repelling, changing color, or cooling down ions.

Answer:

To accelerate the ions