1. How can you measure the volume of solid objects?
Chapter 2.5
How can you measure the volume of solid objects?

2. Short review What is the unit of volume in the metric system?
Answer: liter (L)
The liter is too large a unit to use in the lab so scientists often use the milliliter.
1mL = 1cm3
To measure the volume of a liquid,
you can use a graduated cylinder.

3. Shapes
Regular
Irregular

4. Measuring the Volume of Solid Objects
We already learned that…
volume of a box= length x width x height
volume of a liquid is measured by using:
mass of liquid = mass of beaker and liquid – mass of beaker
What do we do if the shape of the solid object is irregular???

5. Displacement of Water
Displacement of water - is a method of measuring volume of irregularly shaped objects

6. Using Displacement of Water for irregular objects
Pour water into a graduated cylinder. Record the volume of the water.
Place the object in the cylinder. The water level will then rise. Record this new volume.
Subtract the volume of the water from the volume of the water and the object. The difference will be the volume of the object.

7. Example The volume of the water is 10 cm3
The volume of the water and the object is 16 cm3
The volume of the object is 16 cm3-10cm3 = 6 cm3

8. Shapes Regular shape Irregular
Volume = volume of water plus object – volume of water
Volume = length x width x height

9. Self Check- page 41
What is the volume of an object 10 cm long, 5 cm wide and 2 cm high?
A stone is placed in a graduated cylinder, which has been filled to the 35-mL mark. The level rises to 42 mL. What is the volume of the stone?
A red marble is placed in a graduated cylinder, which has been filled to the 25-mL mark. The level rises to the 41 mL mark. A blue marble is placed in another graduated cylinder, which has been filled to the 25-mL mark. The level rises to the 52 mL. Which marble has the greater volume?