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Volume is a measure of the amount of space that something fills.

  • Volume can be measured in the following ways:
    • If an object is rectangular, the length, width, and height can be measured directly with a metric ruler. The three numbers multiplied together give the volume in cubic centimeters.
    • For irregularly shaped solids, water displacement can be used. The volume of a certain amount of water in a graduated cylinder or other measuring device is first measured. The object is dropped in. The change in water level is its volume.
    • If an overflow jar is available, the jar is filled; a graduated cylinder is placed under the spout, the object is dropped in, and the overflow is measured.
    • The volume of containers can be measured indirectly by filling them with water, then pouring the liquid into a graduated cylinder or beaker for measurement.

    Useful hints for measuring volume:

    • The smaller the graduations on the measuring device the more accurate your measurement will be. A milliliter is the same amount of volume as a cubic centimeter.
    • The volume of air in sand can be calculated by adding 40 ml of water to 40 ml of dry sand. The water will fill the air spaces in the sand, and the top surface will be at about 65 ml. Since it would have been 80 ml without the air, the air must take up 15 ml of the sand. By dividing the volume of air by the volume of dry sand, the percentage of air in sand is found.
    Question: Once you find out how to measure mass and volume, can you determine how much air is in the sand?
    Hypothesis: Write your own idea about how you can find out how much air is in sand.

    Materials:

    • Small rock
    • Marble
    • Wood block
    • Baby food jar or any small container
    • Two graduated cylinders
    • Ruler
    • Sand
    • One 50 mL beaker
    • One 250 mL beaker
     
    Safety concerns: icon Be sure to follow all glassware safety rules that are specified by your teacher in all general laboratory experiences. Because graduated cylinders may break, make sure the rocks are not too big to fit in the cylinders. Tilt the graduated cylinders at an angle and slide the marbles or pebbles down the sides for the water displacement method. This will reduce the amount of splash produced and reduce the chances of the graduated cylinder breaking. Remember you should not put a stopper into any flask unless given direct instruction by your teacher.
     

    Procedure:

    1. Use the ruler to directly measure the length, width, and height measurements to find the volume of the wood block.
      • Be sure to use centimeters (cm) so that the volume measurements will be easy to compare with the fluid volume measurements.
      • Remember that the volume of any box shape is l * w * h, or length * width * height.
      • Place the wood block on a balance to determine its mass in grams.
    2. Use the graduated cylinder and the water displacement method for finding the volume of the marble:
      • Place the marble on a balance to determine its mass in grams.
      • It doesn't matter how much water you start with, just leave room for it to rise.
      • Record the starting volume of water.
      • Drop the marble into the graduated cylinder. To reduce the amount of splash and to avoid breaking the cylinder, tilt the cylinder on an angle and slide the marble down the side into the water.
      • Record this final volume in the data section.
      • Subtract the beginning volume from the final volume. The difference is the volume of the marble!
    3. Repeat the same steps above to find the volume of the small rock. Record your data as you go.
    4. Use direct measurement to find the volume of the baby food jar:
      • Place the empty baby food jar on a balance to determine its mass in grams.
      • Fill the jar with water.
      • Place the filled baby food jar on a balance to determine the mass of the jar and the water. Subtract these two numbers to find the mass of the water in the jar.
      • Pour the volume of water into a graduated cylinder, and record its volume.
      • If the jar can hold more water than the graduated cylinder, place as much water as you can measure into the cylinder, record the volume, pour out the water into the sink, and measure the rest of the water in the jar. Add these volumes together for a final volume measurement.
    5. To find the volume of air in sand:
      • Place an empty 50 mL graduated cylinder on a balance and record its mass in grams.
      • Measure 20 mL of sand into the graduated cylinder.
      • Place the graduated cylinder with sand onto a balance and record its mass in grams.
        • Subtract these two numbers to determine the mass of the sand.
      • Measure 20 mL of water into a graduated cylinder.
      • Carefully pour the sand into the water in the graduated cylinder. Try not to get any sand stuck on the sides.
      • Allow the sand to completely submerge in the water. Make sure there are no air bubbles left.
      • The total volume of the sand and water should be 80 mL, since you added 40 mL of one into 40 mL of the other. Record the final volume of the sand/water mixture. If there is a difference between the final volume and 80 mL, this difference is the volume of air in the sand.

    Data:

    1. Wood block:

    • length__________ cm
    • width__________ cm
    • height__________ cm
    • volume (l*w*h) = __________ cm3

    2. Marble (using graduated cylinder):

    • final volume of water__________ mL
    • beginning volume of water__________ mL
    • subtract beginning from final
    • volume =__________ mL

    3. Rock (using graduate):

    • final volume of water__________ mL
    • beginning volume of water__________ mL
    • subtract beginning from final
    • volume =__________ mL

    4. Marble (using beaker):

    • final volume of water__________ mL
    • beginning volume of water__________ mL
    • subtract beginning from final
    • volume =__________ mL

    5. Baby food jar =__________ mL

    6. Volume of air in the sand:

    • beginning: sand + water = _____________mL
    • final volume = _____________ mL
    • subtract final from beginning
    • difference = _____________ mL of air in the sand

    Analysis:

    1. Which had the greater volume, the marble or the rock?
    2. Which had the greater volume, the wood block or the baby food jar?
    3. How close were the volume measurements for the marble using the graduated cylinder and the beaker in the water displacement method? Which method do you feel is most accurate?
    4. What percentage of the sand is air? Divide air space (from #5) by amount of sand (40 mL) and multiply by 100%.
    5. What is the relationship between mL and cubic centimeters?
    6. Which volume measurement method would you use to find the volume of:
      • a glass of milk?
      • a book?
      • a pencil?
    7. What are two things that you learned from this lab?
    8. Which method was the easiest to use?
    9. Which was the hardest method to use?

    Review science safety rules here.

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    Updated October 24, 2008 by: Glen Westbroek

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