Q56 E - Chemistry (OpenStax)

Question

Classify the following sets of measurements as accurate, precise, both, or neither. 

(a) Checking for consistency in the weight of chocolate chip cookies: 17.27 g, 13.05 g, 19.46 g, 16.92 g 

(b) Testing the volume of a batch of 25-mL pipettes: 27.02 mL, 26.99 mL, 26.97 mL, 27.01 mL

 (c) Determining the purity of gold: 99.9999%, 99.9998%, 99.9998%, 99.9999%

Step-by-Step Solution

Answer

(a) Neither

(b) Precise but not accurate 

(c) Both 

Step1: Definition of Accuracy:

Accuracy is defined as the degree of closeness of the measurements to the true value or reference value.

Step 2: Definition of Precision:

Precision defined as the degree of closeness of the measurements with each other.

Step 3: Finding if the given sets are precise, accurate, both or neither: .

(a)  Given set is neither precise nor accurate as measurements are very much varied.

 

b) Given set is precise as it's measurements are close to each other but not accurate because they are far from the true value.

 

c)  Given set is precise as well as accurate as all the measurements are very close to each other and also true value i.e. 100%.