Significant Figures ppt

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Significant Figures

Significant Figures 

All measurements are inaccurate

Precision of measuring device

Human error

Faulty technique

Significant Figures 

Measurements need to convey precision

Must include degree of uncertainty

Sig Figs tell us

Significant Figures

Significant Figures

1.

 

Significant figures in a measurement include all of the digits that are known precisely plus one last digit that is estimated .

Significant Figures

2. Non-zero digits are always significant. 1 0 3 .

23 000 2

Significant Figures

3. All final zeros after the decimal point are significant. 12.74

0 0.042

0

Significant Figures

4. Zeros between two other significant digits are always significant. 1 0 .0

2 00 4 6.

00 0

Significant Figures

5. Zeros used only for spacing the decimal point are

not significant .

1 00 0.00000

233

Always put a 0 in front of a decimal point

0.247

 

0.0042

 

.873

1) 400

3) 0.0001 5) 320 7) 22 568 Significant Figures

2) 200.0

4) 218 6) 0.00530

8) 4755.50

1) 4.0 x 10 3

Significant Figures

2) 1.67 x 10 -8

3) 5 x 10 12 4) 2.00 x 10 4 5) 635.000

7) 5201 6) 22 000 8) 81

Significant Figures

6. If you add or subtract, the answer is rounded to the same number of decimal places as the measurement with the least

number of decimal places.

Significant Figures

7. If you multiply or divide two numbers, the answer is rounded off to the number of significant figures in the least precise term used in the calculation (i.e. the number with the fewest sig figs).

Calculations

Calculations

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