The purpose of a vortex instrument is to mix "small vials of liquids" in a laboratory.
Step-by-step explanation:
A vortex instrument or a mixer is an laboratory instrument which is used to mix liquids in small vials.
The term vortex means swirling of a mass of air and this instrument also mixes liquid through swirling movement inside a tube.
A vortex unit is run by an electric motor which moves a rubber cup attached to the drive shaft.
The rubber cup swirls or oscillates in a circular motion and when a test tube with the liquid is pressed in the cup, the liquid contents get mixed through the transmission of the circular motion from the cup to the liquid. The speed of the rotation can be controlled.