L3: TOOLS OF ANALYTICAL CHEMISTRY

• BOROSILICATE GLASS Pyrex and kimax brands
• BOROSILICATE GLASS most commonly used glassware
• VOLUMETRIC FLASK are calibrated to contain an accurate volume.
• BURET A laboratory apparatus used in quantitative

  chemical analysis to measure the volume of a

  liquid or a gas. It consists of a graduated glass tube with

  a stopcock (turning plug, or spigot) at
• LOWER MENISCUS- CLEAR LIQUIDS

  UPPER MENISCUS- DARK-COLORED LIQUIDS
• KJELDAHL FLASKS Use these for acid digestions.
• KJELDAHL FLASKS They are tilted while heating to avoid

  losses from “bumping”
• TRIPLE BEAM BALANCE Function: To determine Mass of objects
• Weighing bottles are used for drying samples.
• WEIGHING DISH or boat is used for direct weighing of samples.
• DESICCATOR AND DESICCATOR PLATE Use a desiccator to cool a dried or ignited sample.
• DESICCATOR AND DESICCATOR PLATE Cool a red hot vessel before placing in the desiccator.
• DESICCATOR AND DESICCATOR PLATE Do not stopper a hot weighing bottlle (creates a partial vacuum on cooling)
• MUFFLE FURNACE to ignite samples at high temperatures, ex: dry ash organic matter.
• DRYING OVEN Used to dry samples before weighing, Usually 110o C used.
• WASH BOTTLES Use these for quantitative transfer of precipitates and solutions, and for washing precipitates.
• Wash bottles: (a) polyethylene, squeeze type; (b) glass, blow type.
• FILTERING CRUCIBLES Use for filtering non-gelatinous

  precipitates
• Filtering crucibles: (a) Gooch crucible; (b) sintered-glass crucible; (c) porcelain filter crucible.