Significant Figures: Quiz
Nine questions on counting significant figures, rounding, calculations, replicate measurements and accuracy versus precision, with explanations.
Significant Figures: Quiz
9 questions
Leading zeros (0.0) do not count. 3, 0 (between non-zero digits), 5 and the trailing 0 after the decimal point do: 4.
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Answer: 4
Leading zeros (0.0) do not count. 3, 0 (between non-zero digits), 5 and the trailing 0 after the decimal point do: 4.
4.56 cm × 1.4 cm = 6.384 cm². For multiplication, use the fewest significant figures: 1.4 cm has 2, so 6.4 cm².
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Answer: 6.4 cm²
4.56 cm × 1.4 cm = 6.384 cm². For multiplication, use the fewest significant figures: 1.4 cm has 2, so 6.4 cm².
For subtraction, use the fewest decimal places: 2.1 cm has one, so 4.28 cm rounds to 4.3 cm.
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Answer: 4.3 cm
For subtraction, use the fewest decimal places: 2.1 cm has one, so 4.28 cm rounds to 4.3 cm.
The first three significant digits are 1, 2, 3. The next digit is 4 (less than 5), so the 3 stays: 0.00123 m.
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Answer: 0.00123 m
The first three significant digits are 1, 2, 3. The next digit is 4 (less than 5), so the 3 stays: 0.00123 m.
10.0 g ÷ 3.52 mL = 2.8409 g/mL. Both inputs have 3 significant figures, so 2.84 g/mL.
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Answer: 2.84 g/mL
10.0 g ÷ 3.52 mL = 2.8409 g/mL. Both inputs have 3 significant figures, so 2.84 g/mL.
Mean = 4.81 g and standard deviation = 0.008 g, so the readings agree closely (precise). But the error is 4.81 g − 5.000 g = −0.19 g, far larger than the standard deviation (not accurate): a systematic error such as poor calibration.
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Answer: precise but not accurate
Mean = 4.81 g and standard deviation = 0.008 g, so the readings agree closely (precise). But the error is 4.81 g − 5.000 g = −0.19 g, far larger than the standard deviation (not accurate): a systematic error such as poor calibration.
In scientific notation every written digit counts: 3.00 has 3. "300 m" is ambiguous, 0.3 m has 1, and "3000." has 4.
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Answer: 3.00 × 10² m
In scientific notation every written digit counts: 3.00 has 3. "300 m" is ambiguous, 0.3 m has 1, and "3000." has 4.
The dropped part is exactly 5, and the last kept digit (6) is already even, so it stays: 4.36 g. (4.375 g would round to 4.38 g.)
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Answer: 4.36 g
The dropped part is exactly 5, and the last kept digit (6) is already even, so it stays: 4.36 g. (4.375 g would round to 4.38 g.)
Replicates reveal random scatter (precision) and give a better mean. They cannot remove a systematic error: that needs calibration against an accepted value.
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Answer: To calculate a mean and a standard deviation, which show the best value and the precision
Replicates reveal random scatter (precision) and give a better mean. They cannot remove a systematic error: that needs calibration against an accepted value.