Name(s): ____________________________________________________________
pH Lab: Determining the pH of Common Household Items
Be sure that both people in your lab group has this lab completed.
ONE copy of this lab will be graded for a partner grade.
The pH of a solution is a measurement of how acidic or basic a solution is.
An easy way to measure the pH of a solution is to use pH paper. This paper has been treated with
chemical indicators whose color varies according to pH. Another way to measure pH is by using a pH meter.
These meters work by measuring the amount of hydrogen ions in a solution.
Prelab: Understanding the pH scale
1. Examine the pH scale below. This allows us to see how acidic or basic a solution is when we measure
using pH strips.
Acidic
Basic
2. Note that the various colors (ranging from red to blue) and numbers on the scale corresponds to certain pH
values.
3. Answer the following questions before going to the procedure.
a. Which numbers indicate an acid?
b. Which numbers indicate a base?
c. Which number indicates a neutral solution?
d. Which color indicates the strongest acid?
e. Which color indicates the strongest base?
f. Define pH scale:
Procedure
You MUST wear goggles at all times!!!
Take your time on this lab…
Materials:
 Goggles
 pH paper (at each station)
 6 unknown solutions
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
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Paper towels
Droppers (at each station)
Forceps (at each station)
1. Get a pair of goggles and put them on.
2. At each station is a different solution. Record the station number.
3. Using your forceps hold a piece of the pH paper over the paper towel.
4. Use the droppers to Dip your pH paper into the beaker containing the solution. Remove the pH paper right away.
5. Count to 5 and then compare the color of the paper to the color chart.
6. Record your data in the data table below.
7. Throw your paper towel and pH paper in the garbage can before you move to the next station.
8. Repeat for the rest of the solutions at each station.
9. Identify where each solution belongs on the pH scale below:
Station Color of pH pH based on paper reading
Actual
Number
paper
(1-14)
(Acid/Base/Neutral)
Of the solutions you tested, name the:
a. strongest acid: _______________________________________
b. neutral solution: ______________________________________
c. strongest base: _______________________________________