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Designing an Effective Respiratory Cloth Mask Mark as Favorite (61 Favorites)

ACTIVITY in Intermolecular Forces, Molecular Structure, Measurements, SI Units. Last updated January 29, 2024.


In this activity students will use unit conversion to help compare sizes of molecules, viruses, and droplets and then use them to interpret graphical data. They will then use their findings to design a cloth mask that helps protect its wearer against infection by SARS-CoV-2, the coronavirus that causes COVID-19.

Grade Level

High School

NGSS Alignment

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

  • HS-ETS1-1: Analyze a major global challenge to specify qualitative and quantitative criteria and constraints for solutions that account for societal needs and wants.
  • HS-ETS1-3: Evaluate a solution to a complex real-world problem based on prioritized criteria and trade-offs that account for a range of constraints, including cost, safety, reliability, and aesthetics as well as possible social, cultural, and environmental impacts.
  • Scientific and Engineering Practices:
    • Using Mathematics and Computational Thinking
    • Developing and Using Models
    • Analyzing and Interpreting Data


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

  • Compare sizes of molecules, viruses, and droplets, even if sizes are initially given in different metric units.
  • Demonstrate how to use graphical data to solve a problem and understand the relevance of chemistry to practical problems.

Chemistry Topics

This activity supports students’ understanding of:

  • Molecular Size
  • Molecular Structure
  • Intermolecular Forces
  • Measurement
  • Data Analysis
  • SI Units


Teacher Preparation: 50 minutes
Lesson: 90 minutes


Surgical mask (left), N95 mask (right). Images are in the public domain FDA website


  • No specific safety precautions need to be observed for this activity.

Teacher Notes

  • Introduce this activity by discussing with students the recommendations of the CDC and the local health department on how to slow the spread of COVID-19.
  • If available, let students examine both intact and cut examples of N95 respirators, surgical masks, and cloth masks. The cut examples would show students the layers in the respirators and masks.
  • Provide students with the Video Anticipation Guide handout. Students should analysis the questions and select a response to each statement prior to watching the video.
  • Next students should watch the ACS Reactions Video, How Much Do Cloth Masks Protect You From Getting Corona Virus?
  • Following the video, the students should again respond to the statements on the anticipation guide. An answer key has been provided for the teacher, and a class discussion is encouraged.
  • After the video portion has concluded, students should begin the main activity. This portion of the activity can be completed independently by students at their own pace.
  • It might be helpful for the teacher to direct student attention to the bullets points on page 2 of the student handout. These bullets aim to help interpret the data in Figure 2 and 3, and students might benefit from additional teacher instruction related to this information.
  • Providing Figure 2 and 3 in color for students to analyze would be beneficial.
  • The mask design portion of the activity has been labeled as an optional portion. If students participate in this, they might find it to be interesting to share their mask designs with each other. It is important to help students understand that masks need to be used with other measures such as physical distancing and hand washing.
  • Notice to Readers: Permission to reuse figures from ACS Nano 2020, 14, 5, 6339-6347 in this activity was granted by ACS Publications. Further permissions related to the material excerpted should be directed to the ACS.
  • References:

For The Student

Download all documents for this activity, including the teacher guide, from the "Downloads box" at the top of the page.