Education Standards
Serial Dilutions
Overview
Students will be completing a serial dilution to gain a grasp of the parts per billion nanotechnology concepts.
Standards
N.O.S Apply standard techniques in laboratory investigations to measure physical quantities in appropriate units and convert quantities to other units as necessary
Learning Objectives
Students will be able to perform an experiment using safety procedures
Students will investigate what the nano-scale
Students will describe the importance of keeping track of records
Materials
White paper
1 ml dropper
Food coloring
200 ml of water
Rinse cup of water
9 small cups or beakers
1 ml of mouthwash (not to be distributed until the extended section) o Note: any other aromatic scent is fine as well (Vanilla, mint, essential oils)
2 graduated cylinders (10ml)
Student sheet (One in a billion)
Procedure
1. Begin the activity by asking students, which number is larger one billion or one million? Then ask, which quantity is bigger: one part per million or one part per billion? Students may respond that one part per billion is larger because they know that one billion is larger. Some students may understand that one part per billion is smaller than one part per million, however, they may not have an accurate conception of the actual size of one part per billion
2. Ask students Would you prefer to have a concentration of a toxic substance in your drinking water at one part per billion or one part per million. Please explain why. Listen to their responses to get an understanding of their prior knowledge.
3. Ask students to give you some example of things that could represent one billion. They may give examples they learned from the “That’s Huge!” activity, such as, “It would take one billion grains of salt to fill a bathtub.” Write responses on the board.
4. Once you have written down five to six examples of one billion, draw a line beside it to make a two-column chart and write One-billionth a the top of the new column. Tell the students: Many people have a difficult time understanding very large numbers and very small number. In the last activity you learned about very large numbers, numbers in the billions. Today we are going to travel the opposite end of the spectrum and learn about very, very small numbers. After the activity we will complete our chart by filling in examples of one billionth.
5. If students do not already have an understanding of fractions and percents go over “part per” and percents in the teacher background information with them.
Credits
This learning module was created by Bridgette Drake, a participant in Indiana University-Purdue University’s NSF-Funded “Nanotechnology Experiences for Students and Teachers (NEST)” Program (Award # 1513112).