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Stirring Hotplates

Stirring hotplates are devices which contain a large magnet under a heavy, chemical resistent flat surface. The magnet is spun by an electrical motor. This is combined with a hotplate, which can heat a solvent or reaction mixture to the temperature needed to perform a lab procedure. This unit replaces the combination of stir motor + Variac + heating mantle in some of the organic labs.

Stirring Hotplate without block on top

To accommodate round-bottom flasks and heat them evenly, an aluminum heating block can be placed on top of the device.

Stirring Hotplate with block on top

Each has one knob on the front which controls how fast the magnet spins, and another which controls the heating rate. Although they look durable, stir motors can be damaged if mistreated. If they are dropped, especially on their side, the shaft which controls the magnet can become bent, and the stir motor will no longer spin. They must protected from water, since this would ruin the electrical circuitry. The cords are susceptible to damage: do not drop chemicals on the cords, and keep them away from hot surfaces. Always unplug the units by placing your hand directly on the plug and pulling firmly; do not grab the cord and yank it from the socket. The ceramic top can be cracked if the heating block is dropped onto it carelessly, so always use care in moving the block onto or off of your stirring hotplate!

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