significant figures chem 140. why significant figures? weight of penny: 3 g ± 1 g not very accurate...
TRANSCRIPT
![Page 1: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/1.jpg)
Significant Figures
Chem 140
![Page 2: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/2.jpg)
Why significant figures? Weight of penny: 3 g
± 1 g Not very accurate
Weight of truck: 41 057 214 g Also ± 1 g Much more accurate
Cardinal Scale Mfg. Co. Cardinal Scale Mfg. Co.
Cardinal Scale Mfg. Co.
![Page 3: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/3.jpg)
Why significant figures? Measure of accuracy 3 g
Error: 33 % One significant figure
![Page 4: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/4.jpg)
Why significant figures? Measure of accuracy 3 g
Error: 33 % One significant figure
41 057 214 g Error: 0.0000024 % Eight significant figures
![Page 5: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/5.jpg)
Rules for significant figures
1) Nonzero numbers: Always significant
2) Captive zeroes: Always significant3) Leading zeroes: Never significant4) Trailing zeroes: Significant when
the decimal point is written
![Page 6: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/6.jpg)
Examples
13060
![Page 7: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/7.jpg)
Examples
13060 four s.f.
![Page 8: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/8.jpg)
Examples
13060 four s.f.13060.
![Page 9: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/9.jpg)
Examples
13060 four s.f.13060. five s.f.
![Page 10: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/10.jpg)
Examples
13060 four s.f.13060. five s.f.
0.001040
![Page 11: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/11.jpg)
Examples
13060 four s.f.13060. five s.f.
0.001040 four s.f.
![Page 12: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/12.jpg)
Examples
13060 four s.f.13060. five s.f.
0.001040 four s.f.
6.022 × 1023
![Page 13: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/13.jpg)
Examples
13060 four s.f.13060. five s.f.
0.001040 four s.f.
6.022 × 1023 four s.f.
![Page 14: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/14.jpg)
Multiplying and dividing The number with the fewest s.f.
determines how many are in the result.
![Page 15: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/15.jpg)
Multiplying and dividing The number with the fewest s.f.
determines how many are in the result. 0.043 × (6.022 × 1023) = 2.58946 ×
1022
![Page 16: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/16.jpg)
Multiplying and dividing The number with the fewest s.f.
determines how many are in the result. 0.043 × (6.022 × 1023) = 2.58946 ×
1022
= 2.6 × 1022
![Page 17: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/17.jpg)
Adding and subtracting Don’t count significant figures,
count decimal places.
![Page 18: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/18.jpg)
Adding and subtracting Don’t count significant figures,
count decimal places. 3.54 + 0.0152 = 3.5552
![Page 19: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/19.jpg)
Adding and subtracting Don’t count significant figures,
count decimal places. 3.54 + 0.0152 = 3.5552
![Page 20: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/20.jpg)
Adding and subtracting Don’t count significant figures,
count decimal places. 3.54 + 0.0152 = 3.5552 3.56
![Page 21: Significant Figures Chem 140. Why significant figures? Weight of penny: 3 g ± 1 g Not very accurate Weight of truck: 41 057 214 g Also ± 1 g Much more](https://reader035.vdocuments.us/reader035/viewer/2022070307/551aa8485503466b3a8b5b90/html5/thumbnails/21.jpg)
Exact numbers Some numbers have infinite s.f.
60 seconds in a minute 2.54 cm in an inch 2 measurements being averaged