Glassware

Glassware---

Composition

 •Usually manufactured from borosilicate glass. 

•It is resistant to the action of chemicals with the exception of Hydrofluoric acid. 

•It is made of withstand (সহ্য করা) mechanical breakage and a sudden change of temperature. 

•Ingredient-

  Silica (SiO2) --- 80.6%

  Boric oxide (B2O2)  --- 12.6%

  Sodium oxide (Na2O) --- 4.15%

  Aluminium oxide (Al2O3) --- 2.2%

General Glassware

•Beakers:

Capacities from 5 ml to 5000 ml (5 litre). Used mainly for the preparation of solutions.

•Flasks:

Capacities of 25 ml to 5000 ml. 

Different types of flasks is - 

i) Conical flasks(Erlenmeyer type):  Used for performing titrations and for boiling the solution. 

ii) Flat bottomed round flasks: Used mainly for heating liquids. 

iii) Round bottomed flasks: These can withstand higher temperature. They may be heated in a naked flame or in an electrothermal mantle. 

iv) Volumetric flaks: Mainly used to make final volume of the reagent very accurately. 

•Measuring Cylinder:

Available in 10-2000 ml capacities. They are used to measure quantity of the liquid. A high degree of accuracy is not possible because of their wide bore. 

•Bottles: 

i) Reagent Bottle: Available in 25-5000 ml capacities. Made up of plain glass or amber colored glass(Amber colored bottles are usefull to store certain reagents like silver nitrate which are light sensitive). 

ii) Screw Capped Bottles: Available in 5-1000ml capacities. Caps may be made up of metal or plastic. Very good to store hydroscopic reagents. 

iii) Winchester quart bottles: 2000ml capacities. Usefull for storing stock solutions and reagents and also for storing specimen like urine (24 hours collection). 

iv) Drop Bottles: 50-100ml capacities. Used for delivery of drops of solutions, such as stains. 

•Burettes:

Used for measuring variable quantities of liquid. 

•Condensers:

These are available in variable sizes and used for distillation and for reflux operations. 

•Desiccators: 

Chemicals like  sulfuric acid, Phosphorus pentoxide, calcium chloride and Silica Gel can be used as desiccants. The desiccators are mainly used to desiccate chemicals used for the preparation of accurate normal solution and standards. 

•Funnels: 

These are used for the separations of solids from liquids, liquids from liquids for boring liquid, Chemicals or solutions into a container. The commonly used finals are of diameters of 50, 65, 75 and 100 mm