Science
Fourth Hour A
MRS. REYNOLDS

Acids, Bases, and Neutrals pH Scale Investigations
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By Dominic Krusniak

Our Experiment
We were challenged to test the accuracy of cabbage juice as an indicator for classifying liquid solutions as an acid, base, or a neutral.
We believed that red cabbage juice would be an accurate indicator for classifying liquid solutions. We came to this conclusion because we had

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reviewed other reports testing red cabbage juice in a similar way to our method with an outcome in agreement to our hypothesis.
We tested our hypothesis by gathering two tablespoons of the liquids: dish soap, ammonia, baking soda, tea, pop, lemon juice, and vinegar. We poured them into separate, clean plastic cups. We scooped two tablespoons of the cabbage juice solution into each chemical and then we observed the color changes (see the data table below).

Name of
Chemical

Dish
Soap

Ammonia Baking
Soda

Color
Changed

Green Green
Blue

Green

Tea

Pop

Cream of Tatar solution Grey Pink Rose
Pink
Pink

Lemon
Juice

Vinegar

Dark
Pink

Dark
Pink

We claim that all of the chemicals which turned a green or blue color (i.e. dish soap, ammonia, and baking soda.) were bases. Therefore, we also said that all of the chemicals that turned pink or red, where acidic. (i.e.
Tea,soda,cream of tatar solution,lemon juice, and vinegar.)
The above mentioned facts support our hypothesis. In an article we read to begin our lab, we learned about pH and the pH scale. We read that pH was a ranking that classified things as acidic or basic. The pH scale is a scale that gives chemicals a number or place on how acidic or how basic a substance is. On the scale numbers 1-6 are acidic. The numbers 8-14 are considered basic.The number 7 is considered a neutral or non basic nor acidic. We read that lemon juice was number 2 on the scale which is

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acidic. When the lemon juice was tested with the cabbage juice, it turned bright pink. We assumed that all of the other substances that turned pink were also acidic. Ammonia on the pH scale is 11 which is basic and ammonia turned blue. Therefore, we also inferred that all of the other substances that turned a blue or green color were also basic. We also learned that when chemicals are exposed to litmus paper they turned red if they were acidic ,or blue if they were basic.

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In conclusion, we decided that, red cabbage juice was an accurate indicator of classifying substances as a acid,base,or a neutral.
We

discovered that different colors classify different acidities. We also discovered that the vibrance of the color also corresponded to the measure of how acidic or basic the substances are.