Watch Glass
A Watch Glass is a circular concave piece of glass used in chemistry as a surface to evaporate a liquid, to hold solids while being weighed, for heating a small amount of substance and as a cover for a beaker. The latter use is generally applied to prevent dust or other particles entering the beaker; the watch glass does not completely seal the beaker, so gas exchanges still occur. When used as an evaporation surface, it allows closer observation of precipitates or crystallization, and can be placed on a surface of contrasting color to improve the visibility overall
Available in:
- diameter φ70mm
- diameter φ90mm