Litmus

Litmus

Litmus is a water-soluble mixture of different dyes extracted from lichens. It is often absorbed into filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. In an acidic medium, blue litmus paper turns red, while in a basic or alkaline medium, red litmus paper turns blue. In short, it is a dye and indicator which is used to place substances on a pH scale.

Litmus (Battlestar Galactica)

"Litmus" is the sixth episode of the reimagined Battlestar Galactica television series. In the episode, an investigation into a Cylon infiltration comes to focus on the relationship between Chief Galen Tyrol and the Galactica copy of Boomer in order to weed out other sleeper agents.

litmus

Noun

1. A dyestuff extracted from certain lichens, that changes color when exposed to pH levels greater than or less than certain critical levels.
2. A simple test of acidity in a liquid using litmus, usually in the form of litmus paper.