pH Test Lab/Block I/Purcell

pH Test Lab

Problem:
    Find the pH level of several substances.
Hypothesis:
    The acidic substances will turn the litmus paper red and the basic substances will kepp the litmus paper blue.
Materials:
    household solutions
    vinegar
    lemon juice
    blue litmus paper
    computer
    Vernier computer interface
    LoggerPro
    Vernier pH sensor
    wash bottle
    distilled water
    ring stand
    sensor soaking solution
    7 small test tubes
    paper towel
    stirring rod
    red cabbage juice
    250 mL beaker
    diet soda
    milk
    graduated cylinder
    small sticky notes
Procedures:
    First, find goggles and wear them throughout the entire lab. Next, label the test tubes with what substance will be put in it. Then, fill the first tube will 3 mL of vinegar. Next, use the stirring rod to put a drop of vinegar on a strip of litmus paper. Next, try to match the color of the paper with colors on the pH scale. Next, record the information. Then, repeat these steps with every other substance. Then, put 3 mL of distilled red cabbage juice into the vinegar. Next, record the color that the liquid turned. Next, repeat these steps for the rest of the substances. Next, put the pH sensor into a test tube with vinegar. Then, record the pH level that LoggerPro stops at. Then, clean off the pH sensor. Next, repeat these steps with the rest of the substances.
Results:
    

Substance	Blue Litmus	Cabbage	Sensor
vinegar	pH of 2	pink	pH of 2.8
ammonia solution	pH of 11	green	pH of 11.3
lemon juice	pH of 3	pink	pH of 2.5
diet soda	pH of 3	orange	pH of 3.8
drain cleaner	pH of 5	yellow	pH of 12.6
detergent	pH of 10	green	pH of 9.6
baking soda	pH of 9	teal	pH of 8.4
milk	pH of 13	purple	pH of 7

Conclusion:
    I accepted my hypothesis because the litmus paper and the cabbage juice turned warm colors when acidic and cool colors when basic. The litmus paper was accurate for the most part. The cabbage juice was accurate. The sensor was extremely accurate. This was a great and fun experiment.