he food dyes must have had a negative charge in order to move towards the positive end of the electrophoresis chamber.
Explain the reasoning
The movement of molecules in electrophoresis is driven by the application of an electric field, which causes charged molecules to migrate towards the electrode of the opposite charge. In this case, the positive end of the electrophoresis chamber would attract molecules with a negative charge.
Food dyes are often synthetic or natural compounds that contain various functional groups which can exhibit a charge under certain conditions. In the case of electrophoresis, molecules with a negative charge would be expected to move towards the positive end of the chamber.
Therefore, it can be concluded that the food dyes used in the experiment must have had a negative charge in order to migrate towards the positive end of the electrophoresis chamber.