When filling a burette for a titration, adjust the burette so that, preferably over a sink. Then, to add the titrant into the burette. The titrant should be filled.

Explanation:

When filling a burette for a titrant, adjust the burette so that the opening is near or below the eye leve preferably over the sink.

Then, use a funnel to add the titrant into the burette.

The titrant should be filled almost to the zero mark.

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