Question

Why is it important to make sure there are no air bubbles in the tip of a buret below the stopcock before using the buret to dispense a solution? What would be the % error if there were a 0.5 mL air bubble in the tip of a buret, and this air bubble was dislodged when the buret was used to dispense a 20.00 mL sample?

Answer 1

You will deliver only 19.50 (20.00 - 0.50 = 19.5 mL)
You made an error (0.50/20.00)*100 = ?
By the way, I think you made a typo. Most air bubbles don't occupy that much space. I might think 0.050 mL