Weight of Water

1
Weight of Water
2
Introduction

• Purpose or Problem
• Background
• Hypothesis

3
Purpose

• Determine the mass of water using different
  measuring devices.
• Record Data in a proper data table.
• Show sample calculations for average deviation
  and percent deviation.
• Graph Data in a proper format.
• Show proper calculations for mean, average
  deviation, and percent deviation.
• Verify which instrument is more precise.

4
Background

• All Measurements contain error due to
• Imperfect Equipment
• Estimation of final digits
• Scientists record only significant digits in a
  measurement.
• Significant digits are all of the certain digits
  plus one uncertain digit (guess).
• This indicates the precision of the measurement.

5
Hypothesis

• If precision is dependent on the smaller markings
  on the instrument
• Then when the same amount of water is measured
  using differing instruments and weighed using the
  same balance
• It is expected that the instrument with the
  finest gradations will give the most consistent
  results, having the lowest average and percent
  deviation.
• Predict which of these instruments will give the
  lowest percent deviation by ordering them from
  the least to most precise 10.ml graduate, 50ml
  beaker, 100ml graduate, 10.0ml pipette AND GIVING
  YOUR REASONS FOR THE ORDER.

6
Methods
7
Materials

• 10.ml graduate,
• 50ml beaker,
• 100ml graduate,
• 10ml pipette
• Water
• Balance

8
Procedure

• Use the 100ml graduated to measure out 35.2 cc of
  water into a beaker.
• Come up with a procedure to find the weight of
  the water.
• Develop a data table for recording all of the
  data needed to repeat this this calculation 3
  times, in addition to recording the mean, the
  average deviation and the percent deviation.
• Find and record the weight and report it to the
  teacher along with your procedure and data table.
• Repeat the same measurement 3 times with
  different people operating the equipment each
  time.
• Repeat the procedure using the 10ml graduate, the
  10ml pipette, and the 50ml beaker.

9
Procedure

• Compare your Procedure to the one listed below.
• Weigh your graduated cylinder.
• Record the mass.
• Add the water to the proper level.
• Weigh the water Cylinder.
• Record the mass
• Subtract the weight of the cylinder.
• Record the mass of the water only.

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Results Mass of Varying Volumes of WaterMake a
table for each instrument
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Results Data Table (see making a data table)

• Volume Mass for own data.
• Volume and Mass for everyones data.

12
Results Analysis

• Plot a graph of the volume of water vs. the mass
  of the water for everyones data.
• Plot the mean using a different symbol and draw a
  best fit curve for the mean.

13
Conclusions

• Explain any variations in the data.