A spin bar, or stir bar, is a 1 inch long white Teflon-covered magnet. These bars have only one purpose: to stir solutions. They are used in conjunction with a stir motor. You place the spin bar in a container of liquid, then place the container over a stir motor. When you turn the stir motor on, the bar spins and the liquid is stirred.
Spin bars tend to "stick" to anything metal in your lab drawer. Thus, they are often hard to find. Past experience has taught the management to record each time a student comes to the stockroom to obtain a spin bar. If we do not do this, the spin bars end up strewn about the lab, stuck to rings, ring stands, down drains . . . etc. Charging students for these small items, encourages students to search for their lost spin bars.
One place many spin bars is lost is in the waste or used acetone containers. Students dump an unneeded reaction mixture and throw the spin bar out with the waste liquid. Prevent this from happening by using a spin bar retriever. These are Teflon-coated long rods with a magnet at the end; dip them into a solution containing a spin bar and the spin bar will stick to the rod and be lifted out of the container.
See also:
Location: Student lab drawer equipment.
Cost: $1.70
