Floral litmus solutions

Physical Science SC 130 laboratory thirteen collected flowers and boiled them to generate floral litmus solutions. Some flowers generate solutions that function both as red and blue litmus paper simultaneously - that is they change to two different colors when a base or acid is added to the floral litmus solution.

 

Episcia cupreata proved to be an inconsistent indicator, not always changing in the same way for different bases

Baking soda was used to determine whether a floral litmus solution changes color in the presence of a known base. Baking soda is the known base. The students use a variety of local key limes as the known acid.

 

Boiling flowers

Chemistry is a quick run from proton and electrons, basics of atomic structure, hydrogen to oxygen, and then the structure of hydrogen and hydronium ions, providing an attempt at a segue into this laboratory. This material always reminds me that physical science is a bizarre course, an assembled beast that has way too much material in it.

 

Jerisse Salvador

 

A salmon color usually results from the presence of excess hydrogen ions - an acidic solution. Flowers that work as floral litmus solutions tend to turn magenta, pink, or red hues in the presence of acids. In the presence of bases the solution may turn blue, steel blue, green, dark blue-green-gray, or almost black.

 

Lynnsey Sigrah tests unknowns

Once the students have either one litmus solution that detects acids and bases, or two solutions one which detects bases and one which detects acids, the students use their solution to identify whether unknown materials are acidic, basic, or neutral.

 

Viola, Gisele, Midson