Question

The following data is taken from an experiment of measuring the atomic mass of an unknown
substance

Trial

1

2

3

Atomic Mass

10.25 g

2.36 g

29.56 g

The actual value of the atomic mass of the substance is 61.78 g. Which of the following is the most
correct about this data?
answers:
The data is accurate and precise

The data is neither accurate nor precise

The data is accurate but not precise

The data is precise but not accurate

Answer 1

To evaluate the data in terms of accuracy and precision, we need to understand the definitions of these terms:

- **Accuracy** refers to how close a measured value is to the actual (true) value.
- **Precision** refers to how reproducible the measurements are, or how close the measurements are to each other.

Given the data:
- Trial 1: 10.25 g
- Trial 2: 2.36 g
- Trial 3: 29.56 g

The actual value of the atomic mass is 61.78 g.

1. **Accuracy**: All measured values (10.25 g, 2.36 g, and 29.56 g) are far from the actual value (61.78 g), so the data is not accurate.

2. **Precision**: The measured values are not close to each other either (10.25 g, 2.36 g, 29.56 g), indicating that the data is not precise.

Based on this analysis, the most correct statement about the data is:

**The data is neither accurate nor precise.**