Is Electromagnetism the Force Behind Dye Movement in Electrophoresis?

[RED119]

So there was a question on this sheet in my biology class which asked what main force is responsible for the movement of dyes (these dyes had a formal charge and were all water soluble, and were small molecules). I answered electromagnetism. This was marked wrong and he said it was wrong because they aren't like magnets, it is more of an attraction to a large electric charge. I could just be stupid but is that not what electromagnetism is? The interaction of charged particles, magnetic fields and electric current?... Did he just not know what electromagnetism was or am I in the wrong here?

 

[Borek]

I agree with your teacher, no magnetism here, only electric forces.

In a way you are right that electric interactions are part of a larger system of interactions, but there is no need to describe the phenomenon using the most general theory. When you call for electromagnetism here it sounds as if you were guessing.

 

[RED119]

I agree with your teacher, no magnetism here, only electric forces.

In a way you are right that electric interactions are part of a larger system of interactions, but there is no need to describe the phenomenon using the most general theory. When you call for electromagnetism here it sounds as if you were guessing.

But electromagnetism is responsible for the charge of the molecules, their and their movement in the electric field. When the question asked what force was responsible for the movement it seemed like it was looking for a the general force that caused it. Especially when friction wasn't a factor due to the size and solubility of the particles.

 

[Borek]

Especially when friction wasn't a factor due to the size and solubility of the particles.

Quite the opposite, friction due to viscosity (as described by the Stoke's law) is an important factor here.

As I said before: no magnetic counterpart to the process, Coulomb forces are perfectly enough to explain the drift.

 

[Ygggdrasil]

In the context of the four fundamental forces (strong, weak, electromagnetism, gravity), I agree that electrophoresis falls under the category of a phenomena involving the electromagnetic force.

 

[Borek]

In the context of the four fundamental forces (strong, weak, electromagnetism, gravity)

Question is whether it is a convenient context to discuss observations in this case.