Parts Per MillionStudent Lab Procedure
Name____________________________________________________ Date___________________
Gather the Following Materials:
 Safety goggles and gloves
 Chemplate
 Medicine dropper
 Paper Towel
 15-20 mL tap water
 Small cup of water for rinsing dropper
Lab Procedure:
1. Be sure to wear your safety goggles and gloves!
2. Answer pre-lab questions as directed by your teacher. Be prepared to discuss
together as a class.
Pre-Lab Questions:
1.
What is the definition of concentration?
2.
Where in our daily lives do we see and use ppm?
3.
What is the definition of dilution?
4.
How is serial dilution different from dilution?
5.
If you have a 10% solution of food coloring, how many parts are water and
how many parts are food coloring?
3. Place a small piece of white paper under your Chemplate. Fill the large oval
cup in your Chemplate half full of tap water. Put some extra tap water in a
small container (cup) for rinsing your dropper.
4. Your teacher will place 6 drops of food coloring in cup 1.
5. Using your dropper, remove one drop of food coloring from cup 1 and add it to
cup 2.
6. Rinse your dropper thoroughly and add 9 drops of clean water to cup 2 from
the oval cup in your Chemplate mixing thoroughly.
7. Using your dropper, remove one drop of solution from cup 2 and add it to cup
3.
8. Rinse your dropper and add 9 drops of clean water to cup 3 from the oval cup
in your Chemplate mixing thoroughly.
9. Repeat the procedure for cups 4-9.
10. Record the colors of the solutions in the Student Data Table 1.
11. Record the concentrations of each cup in the Student Data Table 1.
Remember…..Cup 1 is a 1/10 concentration.
12. Follow your teacher’s directions for clean up and return all materials.
13. Answer the post lab questions.
Post-Lab Questions:
1. What is the number of the cup in which the solution first appeared colorless
and what was the concentration of the solution in this cup?
2. Do you think there is any food coloring present in this cup even though it is
colorless?
Explain
3. Can you think of an experiment you might do with the solutions to see what
might be present if the water was removed?
4. Would it make sense for pollutants to be described in “parts per ten or parts per
hundred?” Explain your reasoning.
5. Predict how many cups it would take to reach 1 part per trillion (ppt)?
Parts Per Million – Student Data Table 1
Cup
Color
Concentration
Process
Parts Per
Fraction
Decimal
1
10
1 part per 10
1
10
0.1
1
100
0.01
1
2
(Fraction from previous cup)
1 1
x
10 10
3
1 1
x
? 10
4
1 1
x
? 10
5
1 1
x
? 10
6
1 1
x
? 10
7
1 1
x
? 10
8
1 1
x
? 10
9
1 1
x
? 10
1 part per 100
Parts Per MillionSome Interesting Comparisons

One part per million is one second in 12 days of your life!

One part per billion is one second in 32 years of your life!

One part per million is one penny out of $10,000!

One part per billion is one penny out of $10,000,000!

One part per million is one pinch of salt on 20 pounds of potato
chips!

One part per billion is one pinch of salt on 10 tons of potato
chips!

One part per million is one inch out of a journey of 16 miles!

One part per billion is one inch out of a journey of 16,000 miles!

One part per trillion is a six inch leap on a journey to the sun!

One part per billion is one square foot in 36 square miles!

One part per trillion is a postage stamp on an area the size of
Texas!

One part per million is approximately one bogey in 3,500 golf
matches!

One part per billion is approximately one bogey in 3,500,000 golf
matches!

One part per million is approximately one bad apple in 2,000
barrels!

One part per billion is approximately one bad apple in 2,000,000
barrels!

One part per million is approximately one lob in 1,200 tennis
matches!

One part per trillion is approximately one error among all the
words of all the front page stories in all the issues of more than
2,000 daily newspapers in the United States if their publication
had started with the invention of moveable type for the printing
press!