Significant Figures and Density

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Significant Figures and Density
General Chemistry 101/102Laboratory
ManualUniversity of North Carolina at Wilmington
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Significant Figures and Density
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Significant Figures and Density
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Significant Figures and Density
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Significant Figures and Density

• Significant Figures in Calculations

• Addition Subtraction The number of decimal
  places in the answer should be equal to the
  number of decimal places in the value with the
  fewest decimal places.

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Significant Figures and Density
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Significant Figures and Density

• Procedure Part 1 a b

• Pour approximately 8 mL of water into a 50 mL
  graduated cylinder. Record the measured volume
  to the appropriate number of significant figures.
  Repeat the procedure using a 10 mL graduate
  cylinder.

read from the bottom of the meniscus
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Significant Figures and Density

• Procedure Part 1 c d

• Use a 10 mL graduated pipet to transfer 8 mL of
  water to a 50 mL preweighed beaker. Reweigh the
  beaker and use the mass of water and the density
  of water to calculate the volume of water
  transferred.

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Significant Figures and Density

• Procedure Part 2

• Determine the identity of an unknown metal by
  measuring its density (mass/volume). The volume
  of the metal is determined by displacement.

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Significant Figures and Density

• Procedure Part 2

the difference between these two readings is the
volume of the metal