This method is for glassware to be heated at higher temperatures because the flask is warmed indirectly by the hot air collecting under the skirt and unlike simply suspending the glassware, this method is better protected from drafts. The skirt should start at the neck of the flask and drape down to the surface of the plate, not touching the sides of the flask, but covering the majority of the plates surface. Another method, called a teepee setup because it looks a little like a tipi, is to suspend glassware above a plate and surround the flask by a skirt of tinfoil. This works well for low boiling point operations or when a heat source's minimum temperature is high. ![]() This not only reduces the temperature of the glass, but it slows down the rate of heat exchange and encourages even heating. ![]() One method is to suspend glassware slightly above the surface of the plate with no direct contact. Two alternative methods for heating glassware using a hotplate are available. In a student laboratory, hot plates are used because baths can be hazards if they spill, overheat or ignite because they have high thermal inertia (meaning they take a long time to cool down) and mantles can be very expensive and are designed for specific flask volumes. Some hot plates also contain an integrated magnetic stirrer, allowing the heated liquid to be stirred automatically. In laboratory settings, hot plates are generally used to heat glassware or its contents. This laboratory hot plate with magnetic stirrer is used for preparing chemicals used in scientific research.
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