# How does bombarding a molecule with electrons cause ionization?

I am a chemistry student, and my current are of study is mass spectrometry.

In the ionization process, atoms are bombarded with electrons, but how does this work? I assume the flow of electrons attract the electrons of the atom, thereby removing them, but where do the atom's electrons go?

• Electrons do not attract electrons, they would repel each other as they have like charge. – Sherlock Holmes Oct 15 '14 at 1:28
• Imagine the analogy of you holding on to an object (let's say your groceries) then someone chucks stuff at you. You might accidentally drop the groceries. While this is obviously not an accurate analogy on an atomic level, it might help to visualise what is going on. – surelyourejoking Oct 15 '14 at 11:01

This type of ionization is known as electron ionization (there are many types of ionization methods used for MS). One possible reaction for EI is: $$\ce{M +e- ->M^{•+} +2e-}$$ source