scientific notation and significant figures
DESCRIPTION
Scientific Notation and Significant Figures. Why do we use Scientific Notation?. Why do we use Scientific Notation?. Chemists often use very LARGE and very SMALL numbers Examples: Mass of H atom: 0.000 000 000 000 000 000 000 001 67 g Mole of atoms: 602 000 000 000 000 000 000 000. - PowerPoint PPT PresentationTRANSCRIPT
Scientific Notation and Significant Figures
Why do we use Scientific Notation?
Why do we use Scientific Notation?
Chemists often use very LARGE and very SMALL numbers
Examples:
Mass of H atom: 0.000 000 000 000 000 000 000 001 67 g
Mole of atoms: 602 000 000 000 000 000 000 000
Scientific Notation Written as a COEFFICIENT and a
POWER OF 10
Example 1:
2300 = 2.3 x 103
Coefficient
≥ 1 AND <10
Number of times coefficient must be multiplied by ten to get original number
Example 2:
0.0052 =
Example 2:
0.0052 = 5.2 x 10-3
Convert to Scientific Notation
526 000
123
0.0176
624 700 000
0.0010987
19.87 x 10-2
563.28 x 1025
Convert to Scientific Notation
526 000 5.26 x 105
123 1.23 x 102
0.0176 1.76 x 10-2
624 700 000 6.247 x 108
0.0010987 1.0987 x 10-3
19.87 x 10-2 1.987 x 10-1
563.28 x 1025 5.6328 x 1027
Convert to Standard Form
1.26 x 107
4.38 x 10-6
5.9 x 1010
8.6 x 10-13
7.2694 x 103
Convert to Standard Form
1.26 x 107 12 600 000
4.38 x 10-6 0.000 004 38
5.9 x 1010 59 000 000 000
8.6 x 10-13 0.000 000 000 000 86
7.2694 x 103 7269.4
Significant Figures
Scientists report measurements using significant figures
SF: a measurement that includes all the precisely known digits plus a last digit that must be estimated
Measuring using Sig Figs
What is the length of each object?
Sig Fig Rules Every nonzero digit is significant
Zeros between nonzero digits are significant
Zeros in front of all nonzero digits are NOT significant
Zeros at the end of a number and to the right of a decimal are significant
Zeros at the end of a measurement and to the left are NOT significant if there is no decimal at the end
How many Sig Figs?
a. 123 m e. 4.5600 mb. 0.123 m f. 0.078 mc. 40506 m g. 0.070 80 md. 9.8000 x 104 h. 98 000 m
How many Sig Figs?
a. 123 m (3) e. 4.5600 m (5)b. 0.123 m (3) f. 0.078 m (2)c. 40506 m (5) g. 0.070 80 m (4)d. 9.8000 x 104 (5) h. 98 000 m (2)
Addition and Subtraction
The answer can have no more digits to the right of the decimal point than the measurement with the least number of digits after the decimal.
ex. 1 12.52 + 349.0 + 8.24 = ex. 2 740626 - 86.34 =
Multiplication and Division
The answer must contain no more significant figures that the measurement with the least number of significant figure
a. 7.44 m x 0.34 m =b. 2.4526 m / 8.4 =
Practice Problems
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