4. Determine the mass of the water that was poured into the container with the

massing-by-difference approach you learned about previously.

5. Use the known density of the water to calculate the actual volume of water

that was delivered.

Volumes and densities change as the temperature changes, but mass does NOT

change with temperature. You will need to record the temperature in the room

and look up the true density of water at that temperature using the US

Department of the Interior water density table.

Here is an example of what a record of this could look like in your notebook and

the accompanying calculations.

Mass of 150 mL beaker: 240.345 g

Recorded Volume on graduated cylinder: 25.0 mL

Mass of 150 mL beaker containing water: 265.234 g

Mass of water delivered:

Temperature: 20.9 degrees Celsius

Water Density: 0.9980 g/mL

Actual Volume Delivered:

In this case I measured 25.0 mL with the graduated cylinder, but the mass tells

me that I actually poured 24.94 mL of water into the container.

For each of the four tools, complete four trials of measuring 25 mL. There will be

sixteen total trials. The container does not need to be emptied between each trial

for a tool.

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