The following steps should be followed for glassware for which a simple solvent rinse is not sufficient. Follow this by tap water and DI water rinses and air dry. Running solvent through them backwards using gravity (never use vacuum to speed up this process!) can help remove contamination from the inside of the funnel and from the surface of fritted funnels. should be rinsed with an appropriate solvent to remove substances that are clinging to them. In some cases you may need to be more thorough, as described below. Graduated cylinders, beakers, Erlenmeyer flasks, burets and pipettes that were only used to dispense or store reagents generally only need to be triple rinsed with a compatible solvent followed by tap water and a final DI water rinse, if desired. In this way you do not waste time trying to quantitatively clean items that do not need to be. Separate glassware that must be quantitatively clean from that which does not. Triple rinse all surfaces with an appropriate solvent to remove traces of solvents and reaction mixtures, place the rinses in the appropriate waste container. Ground glass stopcocks and stoppers will freeze in place if certain reactants (e. Remove all stopcocks and stoppers from addition funnels, separatory funnels and the like. ![]() ![]() The key to cleaning is doing it a timely manner letting dirty glassware sit for long periods of time guarantees a harder cleaning job.ĭisassemble your apparatus as soon as possible after you are finished with it. Before cleaning be sure that any excess reagent has been disposed of properly and the vessel in which it was contained has been triple rinsed into the waste container. Gloves are recommended, even for general cleaning, if the glassware contained an irritant, lachrymator or toxic material. You must wear eye protection, appropriate for the task, at all times. Glassware that has been cleaned normally is used where a high degree of precision is not required, such as in a synthesis.Įven a task as simple as washing glassware at the sink is potentially hazardous. Normal clean glassware is free of most contamination but some contaminates (e. g., grease) or other impurities on the glassware. At this level of cleanliness there are no residues (e. Quantitatively clean glassware is required for the most demanding applications where a quantity is being measured at high precision, such in analytical or physical chemistry. ![]() There are two broad degrees of clean in chemistry quantitative and normal. ![]() This document is designed to give an undergraduate chemistry student a brief introduction to what chemists mean by “clean” and how it can be achieved. The problem is that the tolerance for shmutz varies with the work you are doing, and sometimes a chemist does not know how important clean glassware is to an experiment until it has failed. The Grasshopper’s Guide to Cleaning GlasswareĪ Chemistry Student approached the Master and asked, Master, how do I achieve enlightenment in Chemistry? The Master replied, Wash your glassware.Ĭlean glassware is essential in chemistry.
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