Significant Figures Study Guide 1.5

An example of an exact number is__________

counting eggs in a carton

Leading zeroes are ____ significant

never

Trailing zeroes are_________ significant unless_____________.

only, they are decimal zeroes

Interior zeroes are always ___________.

significant

The digits 1,2,3,4,5,6,7,8,9 are always________________.

significant

Explain the difference b/w accuracy and precision.

- Accuracy: A measurement is considered accurate if it yields a result that is very close to the true or accepted value. ( Agree with a true value) - Precision: Measurements are said to be precise if they yield very similar results when repeated in the same manner. ( Agree with each other)

When adding or subtracting measured quantities, what determines the number of significant figures in the result?

- Round the result to the same number of decimal places as the number with the fewest decimal places.

When multiplying or dividing measured quantities, what determines the number of significant figures in the result? EX) 1.075 x 10.074 x 0.48=____________

- Round the result to the same number of digits as the number with the fewest significant figures -5.198184 5.198

What are significant figures? Why are significant figures important in science?

- Significant figures: Are any measurement will have a certain amount of significant figures associated with it. That displays how precise it is. - Sig figs are important in science because it allows you to make sure that the answer you get is as precise as possible in any measurements.

1.352 + 0.08 + 12.4471=________

13.88

68cm ________ sig.figs

2

(9.9 x 10^4) + (4.88 x 10^2) +(7.60 x 10^3)=_______________

22.38 x 10^2

0.0596ft________sig. figs

3

186,000 kg________ sig.figs

3

1005in ______ sig.figs

4

0.0045020 lb________ sig.figs

5

2007780 mL__________sig. figs

6

55) Consider the results of the archery contest shown in this figure (a) Which archer is most precise? (b) Which archer is most accurate? (c) Who is both least precise and least accurate?

A is the most precise A is the most accurate b and c are both least precise and least accurate.

51) 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 x 10^-3 F) 0.445

A) 0.44 B) 9.0 C) 27 D) 1.4 E) 1.5 F) 0.45

49) How many significant figures are contained in each of the following measurements? A) 53cm B) 2.05 x 10^8m C) 86,002 J D)9.740 x 10^4 m/s E) 10.0613 m^3 F) 0.17 g/mL G) 0.88400 s

A) 2 B) 3 C) 5 D) 4 E) 6 F) 2 G) 6

53) Perform the following calculations and report each answer with the correct number of significant figures. A) 628 x 342 B) (5.63 x 10^2) (7.4 x 10^3) C) 28.0/13.483 D) 8119 x 0.000023 E) 14.98 + 27,340 + 84.7593 F) 42.7 + 0.259

A) 2.15 (3) B) 42 (2) C) 2.08 (3) D) 1.9 (2) E) 2744 (4) F) 43.0 (3)

45) 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

A) 3 B) 4 C) 4 D) 5 E) 6 F) 3 G) 4

An exact number is ______________

The result of of such a counting measurement