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Working Safely with Glassware. Presented by: Sheryl Hoffmann , B Sc., Grad Dip. O. H . Concordia College. My pet hate. Staged photos with equipment being used incorrectly. Definition.
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Working Safely with Glassware Presented by: Sheryl Hoffmann, B Sc., Grad Dip. O. H. Concordia College
My pet hate Staged photos with equipment being used incorrectly.
Definition A transparent or translucent material, often brittle, usually made by fusion of silica, soda ash, lime and slat cake or similar materials. Other materials are used for various special glasses. Although physically solid, glass is considered by physicists to be A super-cooled liquid, since its structure is not crystalline but amorphous, a characteristic of liquids.
Soda glass vs Borosilicate glass • Soda glass (or ordinary glass) is typically 20% sodium oxide (from soda ash), 5% calcium oxide (from limestone), 70% silica (from sand) and small amounts of other compounds. • Borosilicate glass contains boric acid, which lowers the viscosity of silica without increasing its thermal expansion. These glasses are resistant to thermal stress and have excellent chemical durability. Borosilicate glass is often referred to by trade names such as Pyrex.
Flat glass Sheet glass is made by passing the molten glass through rollers, so some distortion inevitable. Used to glazing greenhouses and garden sheds. Float glass - molten glass is 'floated' onto a bed of molten tin. This produces a glass which is flat and distortion free. Float glass is suitable for fixed and opening windows above waist height. Toughened or safety glass is produced by applying a special treatment to ordinary float glass after it has been cut to size and finished. The treatment involves heating the glass so that it begins to soften (about 620 degrees C) and then rapidly cooling it. Used in low windows (for safety) and for tabletops.
Toughened or Safety glass Ordinary glass when broken Toughened glass when broken
Laminated glass Laminated glass is made up of a sandwich of two or more sheets of glass (or plastic), bonded together by a flexible, normally transparent material. If the glass is cracked or broken, the flexible material is designed to hold the glass fragments in place.
Mirrors Mirrors are usually made from float glass 4-6mm thick, and silvered on one side. Mirrors are available for use without a surrounding frame, these usually are made from a type of safety glass. Old mirrors, and modern mirrors supplied within a frame, should not be used unframed as any damage to them might cause the glass to shatter dangerously.
Two way mirrors: When incorporated into laminated glass, transparent mirror allows for undetected observation proper ambient light ratios are required to maximize the transparent mirror effect. On the light side most of the light is reflected back so the little light being transmitted from the dark side is not observed.
To tell if a mirror is a normal ora two-way mirror: Place the tip of your fingernail against the reflective surface and if there is a GAP between your fingernail and the image of the nail, then it is a GENUINE mirror. However, if your fingernail DIRECTLY TOUCHES the image of your nail, then it is a 2-way mirror.
Laboratory Glassware - 5 main uses • To heat & mix • To store • To transfer • To deliver a specific Volume • To contain a specific volume
To Store Reagent Bottle Specimen Jar Schott Bottles
To store Vented lid for H2O2 Reuse with care
To store & Deliver Polystop bottle Stull Dropper bottle T.K. Pattern
Buchner Flask & Funnel Gooch Rubber
