g If you forgot to fill the tip of the NaOH buret, took your initial reading and then completed the titration, what measurement would be affected

The volume of NaOH used

Explanation:

The tip of the buret is part of its calibration. If this tip is not filled before taking the initial reading, the volume of NaOH used at the end of the titration would be inaccurate.

In order to avoid this, the valve of the buret should be opened and the NaOH allowed to displace whatever air that might have been trapped at the tip before the initial buret reading is taken and the titration is carried out.