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Measurement Tools, Significant Figures and Conversions (17 Favorites)

ACTIVITY in Accuracy, Dimensional Analysis, Measurements, Significant Figures, SI Units. Last updated May 27, 2021.


Summary

In this activity, students will complete several hands-on measurements, using a variety of common measuring tools. They will carefully consider how to properly report each measurement based on the tool used. Students will then complete measurement conversions, and apply their knowledge of significant figures.

Grade Level

High and Middle School

NGSS Alignment

This activity will help prepare your students to meet the performance expectations in the following standards:

  • Scientific and Engineering Practices:
    • Using Mathematics and Computational Thinking

Objectives

By the end of this activity, students should be able to:

  • Identify common laboratory equipment.
  • Understand how to perform dimensional analysis.
  • Apply the conversions needed to switch between metric units and English units.
  • Estimation of data based on measuring devices
  • Demonstrate accuracy and precision in measurement by using significant figures based on a particular measurement device.

Chemistry Topics

This activity supports students’ understanding of:

  • Measurement
  • Accuracy
  • Precision
  • Significant Figures
  • English Units
  • Metric Units
  • Conversion Factors
  • Dimensional Analysis

Time

Teacher Preparation: 10 minutes
Lesson: 30 minutes

Materials

  • Pencil or pen
  • Ruler with inches
  • Paper clip
  • Electronic balances
  • Erlenmeyer flask
  • Graduated cylinders (various sizes)
  • Beaker
  • Water
  • Thermometer
  • Metal sample (irregular object/size)
  • Calculator

Safety

  • Always wear safety goggles when handling chemicals in the lab.
  • Students should wash their hands thoroughly before leaving the lab.
  • When students complete the lab, instruct them how to clean up their materials and dispose of any chemicals.

Teacher Notes

  • This lab is designed to be set up as six stations. Using stations reduces the need for a lot of materials, and reduces the setup time. Alternatively, this activity can be reconfigured by providing each group with everything that is needed to perform the activity.
  • Prior to this activity, I have already taught the students about metric conversions and dimensional analysis. In addition, the students have already learned about significant figures and how to record measurements using significant figures based on the particular measuring device being used. It’s important that students understand that the marks on the measuring device will determine the specific number of digits in a measurement.
  • I make my students memorize time conversion factors (seconds to minutes to hours to days to weeks to years) because I consider that to be a life skill. Depending on the conversion information that you may or may not provide to your students, you can edit the student handout as needed.
  • Students should solve the conversion problems using dimensional analysis.
  • The metal sample used in Station 6 can be any irregular solid that the students need to use water displacement to determine the volume. I use a sample of zinc when I use this activity. Other items like a metal
  • An answer key (using sample data) has been provided for teacher reference.

For the Student

Lesson

In this activity, we will practice the use of significant figures and measurement conversions, as well as become more familiar with common measurement tools used in the chemistry lab.

Each station will have the necessary equipment that you will need to make the measurement(s) described.

  • Use your knowledge of significant figures to report your measurement using the proper number of significant figures, for that particular tool.
  • Make sure that all measurements have units.

Finally, you will complete a conversion and/or calculation involving your data.

  • Indicate the conversion factor that you need in order to complete the calculation (some are given for you).
  • Show your work using dimensional analysis and be sure to use the correct number of significant figures in your final answer.

Station 1: Measure the length of your pencil using the metric side of the ruler (cm).
Record Data: ________ Convert your measurement from metric units (cm) to English units (inches). Show work below using dimensional analysis: Conversion factor: Given: 2.54 cm per inch

Station 2: Weigh the mass of the paper clip in grams and record your measurement. 
Record Data: ________ Convert your measurement to milligrams. Show work below using dimensional analysis: Conversion factor:

Station 3: Measure the volume of liquid in the graduated cylinder, the beaker, and the Erlenmeyer flask. Record all measurements with the correct number of significant figures. 
Record Data Calculate what the volume would be if all three of these amounts were HYPOTHETICALLY added together (don’t actually do it with the real equipment).
Graduated cylinder:
Beaker:
Flask:

Station 4: Take the temperature of your armpit (through your shirt) in oC and record your measurement. 
Record Data: ________ Convert your measurement to Kelvin. Conversion factor:

Station 5: Use your cell phone as a stopwatch to determine how long you can hold your breath…don’t faint! Record your time in seconds. 
Record Data: ________ Convert your time to hours. Show work below using dimensional analysis: Conversion factor:

Station 6: Determine the density of the metal item. (Hint: Think of the units for density. Be sure to measure and record each variable involved.)
Record Data: ________ ________
  1. a. Show all of your work for the density calculation below:
  1. Calculate the percent error in your measurement. (The theoretical density value for the metal is 7.14 g/mL). Show all work: