Errors (CHE 7)

What is a random error?

• results are under the true value

• errors that are randomly planned

• results are over or under the true value

• errors which are unavoidable

What is a systematic error?

• all results are either under or over the true value

• some results are under and over the true value

• errors that are systematically calculated

• errors that can be fixed by calculating an average errors that can be fixed by calculating an average

I have read all my burette readings not at eye level but from above

• Random error

• Systematic error

Misjudging the color of the indicator near the end point

• Random error

• Systematic error

Using wrong amount of indicator for one of the titration

• Random error

• Systematic error

Rinsing burette and/or pipette with distilled water

• Random error

• Systematic error

Not transferring all solid/liquid when preparing samples into a volumetric flask

• Random error

• Systematic error

Leaking burette

• Random error

• Systematic error

Not filling burette properly - there is an air lock in the burette stopcock it can block the flow of the titrant

• Random error

• Systematic error

Losing solution - too vigorous swirling can end in liquid splashing from the titration flask before the end point had been reached.

• Random error

• Systematic error