Measuring Volume & Density

By:

Brianna Shields

September 14, 2005

DO NOW

1. Name the unit used to label mass

2. What is the first step for using a triple beam balance?

3. What tool is used to measure length?

Volume of a liquid

Definition The amount of space a liquid takes up

Volume of a liquid

Tool Graduated Cylinder

Volume of a liquid

Units Milliliters (ml)

Volume of a liquid

Formula Read the volume level from the bottom of the meniscus

Volume of an irregular solid

Definition The amount of space a solid takes up

Volume of an irregular solid

Tool Graduated cylinder

Volume of an irregular solid

Units Milliliter (ml)

Volume of an irregular solid

Formula Measure the difference in water levels

Volume of a cube

Definition The amount of space a cube takes up

Volume of a cube

Tool Metric Ruler

Volume of a cube

Units Centimeters cubed (cm3)

Volume of a cube

Formula Volume = length x width x height

Example

• What is the volume of the liquid at left?

Example

What is the volume of the liquid at left?

What is the volume of the object ?

Example

What is the volume of the cube at left?

Density

Definition The number of particles that can be packed into a space

Density

Tool Graduated cylinder or metric ruler AND triple beam balance

Density

Units G.C. = g/mlRuler = g/cm3

Density

Formula Density = mass divided by volume

D =m/v

Density

How to calculate density

1. Find the mass in g 2. Find the volume in ml or

cm3

3. Divide the mass by the volume

4. Round to the nearest tenth 5. Label answer with correct units

Density of Water

Water’s Density

1.0 g/ml

Density

Sink or Float?

When d > 1.0 g/ml = sinkWhen d< 1.0 g/ml = float

Density

Estimating Density of sinking object is simply > 1.0

Density of floating object = % of object below water level

Density

Cutting an object

Density of a pure substance is always the same regardless of size

Example

• What is the density of the object to the left if m=79.4 g, v= 29.8 cm3?

Example

Which of the objects would sink? Float? Explain

Densities of Common Elements and Compounds

Water = 1.0 g/ml

Methanol= .79 g/ml

Gold 19.30 g/ml

Air= .0013 g/ml

Iron= 7.8 g/ml

Ice= .93 g/ml

Mercury= 13.5 g/ml

Aluminum= 2.7 g/ml

Ethanol= .94 g/ml

Oak= 0.85 g/ml

Example

How would these materials layer in a container?

Densities of Common Elements and Compounds

Water = 1.0 g/ml

Methanol= .79 g/ml

Gold 19.30 g/ml

Air= .0013 g/ml

Iron= 7.8 g/ml

Ice= .93 g/ml

Mercury= 13.5 g/ml

Aluminum= 2.7 g/ml

Ethanol= .94 g/ml

Oak= 0.85 g/ml

Example

Estimate the density of the material at the left

Example

Estimate the density of the material at the left

Example

Estimate the density of the material at the left

Example

This block has a density of 10.0 g/cm3. What is the density of the block at the left if it is cut in half?

Practice

Work with your lab partnerComplete the volume and density

practice questions in your handoutWe will go over the correct answers

next class

Hands On: Volume

Object Tool Work Answer

1. Marble

Graduated Cylinder

Hands On: Volume

Object Tool Work Answer

2. Toy Graduated Cylinder

Hands On: Volume

Object Tool Work Answer

3. Block 1

Ruler V = lxwxh

Hands On: Volume

Object Tool Work Answer

4. Block 2

Ruler V = lxwxh

Hands On: Volume

Object Tool Work Answer

5. Mystery Liquid

Graduated cyclinder

Hands On: Density Object 1

Mass

Volume

Hands On: Density Object 1

Density

Answer

Sink or Float

Hands On: Density Object 2

Mass

Volume

Hands On: Density Object 2

Density

Answer

Sink or Float

Practice: Volume and Density

1a. What is the volume of liquid in the graduated cylinder on the right?

1a. V=

1b. If an object is placed into the same graduated cylinder and the water level rises up to 25 ml, what is the volume of the object?

1b. V=

Practice: Volume and Density

2. Calculate the volume of the cube

2. V=

3. The following measurements are taken of a wood block. Length =2.3cm, width = 6.0 cm, height = 4.2 cm. What is the cube’s volume?

3. V=

Practice: Volume and Density

4. Place the objects where they belong when placed into a container of water

4.

Practice: Volume and Density

5. If a bar of soap has a mass of 57.0 grams and a volume of 112 cm3, what is its density? Label your answer. Will it sink or float in water?

5.