Teacher Notes

Density of Solids

Classroom Set

Materials Included In Kit

Aluminum bars, 15
Aluminum cubes (cube 2), 15
Plastic rulers, metric, 30
Steel cubes (cube 1), 15

Additional Materials Required

Balance, 0.1-g precision

Disposal

All materials may be saved for future use.

Teacher Tips

  • Enough materials are provided in this kit for 15 groups of students. This laboratory activity can reasonably be completed in one 50-minute class period.
  • Additional Density of Solids Kits, AP4615, may be purchased for each individual lab group.

Correlation to Next Generation Science Standards (NGSS)†

Science & Engineering Practices

Planning and carrying out investigations
Analyzing and interpreting data
Using mathematics and computational thinking

Disciplinary Core Ideas

MS-PS1.A: Structure and Properties of Matter
HS-PS1.A: Structure and Properties of Matter

Crosscutting Concepts

Patterns
Scale, proportion, and quantity

Sample Data

{11964_Data_Table_1}

Answers to Questions

  1. How do the densities of cube 1, cube 2 and the bar compare?
    The densities of cube 2 and the bar are equal.
  2. From the data collected, are any of the objects composed of the same material? How do you know this?
    From the calculated density values, cube 2 and the bar have the same density. Therefore, cube 2 and the bar are most likely composed of the same substance.
  3. Use the following density table to identify the material the composes each item.
    {11964_Answers_Table_1}
    {11964_Answers_Table_2}
  4. Once each item has been identified, use the following equations to determine the accuracy of your calculated density measurement. Use the following equation.
    {11964_Answers_Equation_1}
    {11964_Answers_Equation_2}
  5. What are some possible errors in your density calculations?
    Measurement with the ruler, incorrect mass measurement, and imperfect blocks (not perfectly square) are all possible sources of error.

Recommended Products

Item No. Description
AP6148 Density of Solids—Laboratory Set

Student Pages

Density of Solids

Introduction

In this activity, two cubes and a bar that have the same physical appearance will be used to introduce the concepts of volume, mass, and density.

Concepts

  • Measurement
  • Density
  • Percent error
  • Mass
  • Volume

Background

In this activity, the mass, volume and density of two cubes and a bar will be determined and compared by measurement. The volume of any regular solid can be calculated using Equation 1. The length, width, and height must be determined using a metric ruler.

{11964_Background_Equation_1}

Once the solid object’s mass and volume are known, the density may be found using the following equation.
{11964_Background_Equation_2}

Density, which is defined as an object’s mass divided by its volume, is a characteristic property of a material. Solids that have the same physical appearance or objects of different shapes and sizes may be identified by their densities. The density of a solid is commonly expressed as g/cm3.

Materials

Balance, 0.1-g precision
Bar
Cube 1
Cube 2
Plastic ruler, metric

Prelab Questions

  1. Obtain cube 1, cube 2 and the bar.
  2. Pick up cube 1 and cube 2 and note the similarities and differences of each cube. Is one cube heavier than the other one?
  3. Now pick up the Bar and compare it to cube 1 and cube 2. Is the bar composed of the same material as either of the cubes? How can it be determined if the bar is made of the same material as one of the cubes?

Safety Precautions

Although this activity is considered nonhazardous, please follow proper laboratory safety guidelines.

Procedure

  1. Measure the length, width and height of the heavier cube, cube 1, in centimeters. Record the values in the data table.
  2. Using Equation 1, determine the volume of cube 1. Record the volume for cube 1 in the data table.
  3. Find the mass of cube 1 using a balance. Record the mass to the nearest 0.1 g in the data table.
  4. Determine the density of cube 1 by using the calculated volume of cube 1 from step 2 and the mass of cube 1 from step 3 (see Equation 2 in the Background section). Record the density in the data table.
  5. Repeat steps 1–4 for cube 2 and also the bar. Record all information in the appropriate spaces in the data table.

Student Worksheet PDF

11964_Student1.pdf

†Next Generation Science Standards and NGSS are registered trademarks of Achieve. Neither Achieve nor the lead states and partners that developed the Next Generation Science Standards were involved in the production of this product, and do not endorse it.