Question

Why are both accuracy and precision important in making a measurement

Answer 1

It is because precise amount measured is required for the reaction to take place chemically, and an accurate conclusion will prevent any dangerous and misleading conclusions made due to inaccurate data.

For example, in physics, every measurement we state the instrument uncertainty after the measurement, stating that it is not a definite certain measurement, but the smaller the value for the uncertainty, the more precise that instrument's data is.

Precise is important in terms of knowing how many moles or grams of reactant is required for this reaction to complete without any shortage or excess chemically. Accuracy is based on the conclusions we make in regards to the data and observations we make experimentally.