volumetric analysis

Volumetric Analysis

Apparatus

The Volumetric Flask

Volumetric Flask• Weigh out a specific mass of anhydrous sodium

carbonate on a clean, dry clock glass accurate to 0.01g.

• Add the solute to a beaker containing a small volume of deionised water.

• Using a wash bottle wash all traces of the solute from the clock glass into the beaker.

• Stir with clean glass rod to dissolve• Using a funnel transfer the contents of the beaker

into a clean dry volumetric flask.• Wash all traces from the beaker, glass rod and

funnel into the flask.• add deionised water until the level is 1 cm below

the gradation mark.• Using a dropper fill the rest of the volumetric flask• until the bottom of the meniscus is on the mark.

Volumetric Analysis• Stopper the flask and invert about 30 times.

• This ensures the mixture is homogenous.

The Pipette• Rinse with deionised water.

• Rinse with some of the solution it is to contain.

• Use a pipette filler to draw the level of the liquid above the graduation mark and then allow to empty till at bottom of the meniscus.

• Allow to empty with gravity,to remove adhering drop touch off side of glass. Dont blow: its calibrated for this

The Burette

The Burette• Rinse with deionised water.• Rinse with some of the solution it is to

contain.• Use a small funnel when

filling the burette.• The burette is filled almost to the top and

then the tap is opened to fill the part below the tap and so the meniscus is on the bottom of the graduation mark

Conical Flask

Conical Flask• Its design allows it to be swirled without the

solution splashing out.

• Before use, wash out with deionised water.

• Do not wash out with the solution it is to contain

• Can rinse with deionised water during titration because no effect on number of moles in flask

• Place over coloured tile to help see colour change