Accuracy

Definition

Accuracy refers to how close a measured value is to the true or accepted value. It indicates the correctness of a measurement.

5 Must Know Facts For Your Next Test

1. Accuracy is different from precision; accuracy reflects correctness while precision reflects consistency.
2. A measurement can be accurate but not precise if it is close to the true value but not consistently reproducible.
3. Systematic errors affect accuracy because they skew measurements in one direction, away from the true value.
4. Accuracy can be improved by calibrating instruments and using proper techniques.
5. In chemistry, accuracy is crucial for experiments where exact quantities are necessary for reactions.

Review Questions

• How does accuracy differ from precision?
• What type of error most commonly affects accuracy?
• Why is accuracy important in chemical measurements?

Related terms

Precision:

The degree to which repeated measurements under unchanged conditions show the same results.

Systematic Error:

A consistent, predictable error that skews all measurements in one direction, affecting accuracy.

Calibration:

The process of adjusting an instrument to ensure its readings are accurate by comparing with a standard or known value.