1.5 Measurement Uncertainty, Accuracy, and Precision
Exact versus uncertain numbers, counting significant figures in a recorded value, and the rounding rules that keep a computed result honest.
Chemistry 2e, 1.5 Measurement Uncertainty, Accuracy, and Precision
5 exercises
1.5 Exercise 2
Express each of the following numbers in exponential notation with correct significant figures:
(a) 704
(b) 0.03344
(c) 547.9
(d) 22086
(e) 1000.00
(f) 0.0000000651
(g) 0.007157
1.5 Exercise 4
Indicate whether each of the following can be determined exactly or must be measured with some degree of uncertainty:
(a) the number of seconds in an hour
(b) the number of pages in this book
(c) the number of grams in your weight
(d) the number of grams in 3 kilograms
(e) the volume of water you drink in one day
(f) the distance from San Francisco to Kansas City
1.5 Exercise 6
How many significant figures are contained in each of the following measurements?
(a) 53 cm
(b) 2.05 108 m
(c) 86,002 J
(d) 9.740 104 m/s
(e) 10.0613 m3
(f) 0.17 g/mL
(g) 0.88400 s
1.5 Exercise 8
Round off each of the following numbers to two significant figures:
(a) 0.436
(b) 9.000
(c) 27.2
(d) 135
(e) 1.497 10−3
(f) 0.445
1.5 Exercise 10
Perform the following calculations and report each answer with the correct number of significant figures.
(a) 628 342
(b) (5.63 102) (7.4 103)
(c)
(d) 8119 0.000023
(e) 14.98 + 27,340 + 84.7593
(f) 42.7 + 0.259
Adapted from General Chemistry © 2019 Rice University. Licensed under CC BY 4.0. Sources: Chemistry 2e, Chemistry: Atoms First 2e. Imported at revision 32c7196.