On the diagram, label the parts A to D. 1. (c) (ii) State what happens at A, B and C.

Here are the solutions to the questions:

1. (c) (i) On the diagram, label the parts A to D.

• A: $\boxed{\text{Ionization chamber / Ion source}}$
• B: $\boxed{\text{Electric field / Accelerating plates}}$
• C: $\boxed{\text{Magnetic field / Deflection chamber}}$
• D: $\boxed{\text{Detector}}$

1. (c) (ii) State what happens at A, B and C.

• At A (Ionization chamber): The sample is vaporized and then bombarded with high-energy electrons, causing atoms or molecules to lose electrons and form positive ions.
• At B (Electric field / Accelerating plates): The positive ions are accelerated by an electric field to a high, uniform velocity.
• At C (Magnetic field / Deflection chamber): The accelerated ions pass into a magnetic field, which deflects them according to their mass-to-charge ratio ($\text{m/z}$). Lighter ions and ions with higher charges are deflected more.