Question

Using the same triple balance, three students measure the mass of 93 mL of liquid. They record the mass as 95.5 g, 95.0 g, and 96.0 g. Discuss the accuracy and precision of their measurements and any possible sources of error.

A) All measurements are accurate and precise.
B) Measurements are accurate but not precise.
C) Measurements are precise but not accurate.
D) Accuracy and precision cannot be determined.

Answer 1

The mass measurements of the liquid are close to one another, indicating that they are precise. Without the true mass, accuracy cannot be determined, but the variability suggests possible precision with unknown accuracy.

Step-by-step explanation:

When assessing the results of the mass measurements (95.5 g, 95.0 g, 96.0 g) of 93 mL of liquid using the same balance, we must consider both accuracy and precision. Accuracy refers to how close a measurement is to the true or accepted value, whereas precision refers to the reproducibility of the measurements – how close the values are to each other, regardless of their accuracy.

In this scenario, without knowing the true mass of the 93 mL of liquid, we cannot determine accuracy. However, the measurements are relatively close to one another, which indicates that the measurements are precise. The variations within these measurements could be due to errors like the calibration of the balance, the skill of the operator, parallax errors while reading the scale, or environmental factors such as air currents. Thus, the appropriate classification would be C) Measurements are precise but not accurate.