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?
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
It is important to make sure there are no air bubbles in the tip of a buret below the stopcock before using it to dispense a solution due to the following reasons:
1. Accuracy: Air bubbles can affect the volume of the solution dispensed. The presence of an air bubble can lead to an incorrect measurement since the volume of the bubble will displace the solution, resulting in an underestimated volume.
2. Precise Measurements: Burets are commonly used in quantitative experiments where precision is crucial. To obtain accurate and reliable results, it is important to eliminate sources of error, such as air bubbles.
Now, let's calculate the percentage 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:
Percentage Error = [(Volume of air bubble) / (Volume dispensed)] x 100%
= [(0.5 mL) / (20.00 mL)] x 100%
= 2.5%
Therefore, if there were a 0.5 mL air bubble in the tip of the buret and it was dislodged while dispensing a 20.00 mL sample, the percentage error would be 2.5%.
It is important to make sure there are no air bubbles in the tip of a buret below the stopcock before using it to dispense a solution for a couple of reasons:
1. Accuracy: Air bubbles can affect the accuracy of the volume being measured or dispensed. Burets are typically used for precise volumetric measurements in chemistry experiments, such as titrations. If there are air bubbles present, the volume of the solution dispensed may be higher than the intended value, leading to inaccurate results.
2. Consistency: Air bubbles can cause variability in the volume dispensed. If there are air bubbles in the buret, they can disrupt the flow of the solution, causing inconsistent drops or an irregular flow rate. This inconsistency can affect the overall precision of the experiment and lead to inconsistent results.
Now, let's calculate the percentage 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:
Percentage error = (Measured volume - True volume) / True volume x 100
True volume = 20.00 mL
Measured volume = True volume + Volume of air bubble
Volume of air bubble = 0.5 mL
Measured volume = 20.00 mL + 0.5 mL = 20.50 mL
Percentage error = (20.50 mL - 20.00 mL) / 20.00 mL x 100
Percentage error = 0.50 mL / 20.00 mL x 100
Percentage error = 2.5%
Therefore, if there were a 0.5 mL air bubble in the tip of the buret, and it was dislodged during the dispensing of a 20.00 mL sample, the percentage error would be 2.5%.